Update as of 5/23/2012
* Published performance tests (`dev/tests/performance`)
* Implemented support of ImageMagick library for processing images
* Distinguished "Page Fragments" and "Pages" in layout handles declaration
* Reduced performance drop caused by introducing containers
* Implemented Magento_Data_Structure library which is used to handle structure of layout elements
* Fixed some issues:
  * Fixed error on saving newsletter template
  * Fixed some checkout issues:
    * order is not placed if 3D Secure is used
    * transaction is not created if PayPal Standard is used
    * "Purchase Order Number" field is not displayed
    * failed checkout on concurrent user requests
  * Fixed incorrect shipment creation: shipping and tracking information was not saved
  * Fixed broken category page when "Use Flat Catalog Product" is enabled
  * Fixed incorrect applying of discount to a sub-product, if more two rules are being applied
  * Fixed broken "Edit" product link in Wishlist and Shopping Cart
  * Fixed broken installation when "pub/media" is not writable
  * Fixed resetting Design Theme configuration option when User-Agent Exception is added
  * Fixed error while running unit tests, when Zend Framework is installed with PEAR
  * Fixed incorrect processing of "before" and "after" layout instructions in case, when the instruction refers to a node, which is not processed yet
  * Fixed broken import/export functionality
  * Fixed broken Web Services pages in Admin Panel
  * Fixed broken creation of URL rewrite
  * Fixed error in Weee module caused broken view pages of configurable products with recurring profile or downloadable/bundle product
  * Fixed error on submitting XML Connect application
  * Fixed broken design when database is used as media storage
* Other small changes
Update as of 5/31/2012
* Implemented backend authentication independent of `Mage_Adminhtml` module. Authentication can be disabled
  * Authentication logic is moved to `Mage_Backend` module and being performed in controller instead of observer
  * `Mage_Adminhtml_Controller_Action` is changed to `Mage_Backend_Controller_ActionAbstract`, `Mage_Admin_Model_Session` is changed to `Mage_Backend_Model_Auth_Session`, `Mage_User_Model_Role` and `Mage_User_Model_Roles` classes are unified into one `Mage_User_Model_Role` class
  * Introduced `Mage_User` module for users and roles management
* Introduced support of minimized CSS and JS files: in production mode minimized file is used, if exists
* Implemented resize, rotate, crop and watermark functionality for ImageMagick adapter
* Fixed some issues:
  * Fixed absence of product without image, if ImageMagick is used
  * Fixed broken Downloadable product creation page, when developer mode is enabled
  * Fixed random failures of `Integrity_LayoutTest::testHandlesHierarchy` test
  * Fixed backup creation: media directory was excluded from the backup file when it should be included and vice-versa
  * Fixed broken product configuration page in Shopping Cart
  * Fixed incorrect work of "After number of attempts to login" functionality for CAPTCHA: captcha was not displayed after specified number of incorrect attempts
  * Fixed creation of User Role: resource access was set to 'Custom', when 'All' is selected
  * Fixed exception "Unable to locate skin file" at the end of installation
  * Fixed broken "Use Store Credit" functionality on checkout
  * Fixed lost MySQL connection, if it's not used for long time
  * Fixed ability to separate CDN server setup for static and media content
  * Other small fixes
Update as of 6/7/2012
* Fixed various crashes of visual design editor
* Fixed some layouts that caused visual design editor toolbar disappearing, also fixed some confusing page type labels
* Eliminated "after commit callback" workaround from integration tests by implementing "transparent transactions" capability in integration testing framework
* Refactored admin authentication/authorization in RSS module. Removed program termination and covered the controllers with tests
* Removed HTML-report feature of copy-paste detector which never worked anyway (`dev/tests/static/framework/Inspection/CopyPasteDetector/html_report.xslt` and all related code)
* Github requests:
** [#19](https://github.com/magento/magento2/pull/19) Implemented "soft" dependency between modules and performed several improvements in the related code, covered with tests
Update as of 6/20/2012
* Implemented locale translation inheritance
* Implemented new format for exporting customer data
* Added initial Javascript code for globalization and localization
* Added initial Javascript unit tests
* Implemented file signature for urls of static files - better CDN support
* Implemented optional tracking of changes in view files fallback - cached by default, tracked in developer mode
* Introduced `@magentoDbIsolation` annotation in integration tests - isolates DB modifications made by tests
* Started refactoring of Visual Design Editor Javascript architecture
* Github requests:
  * [#25](https://github.com/magento/magento2/issues/25) Removed unused `Mage_Core_Block_Abstract::getHelper()` method
* Fixed:
  * "$_FILES array is empty" messages in exception log upon installation
  * Long attribute table aliases, that were producing errors at DB with lower identifier limitation than MySQL
  * Watermark opacity function did not work with ImageMagick
  * `Magento_Test_TestCase_ControllerAbstract::assertRedirect` was used in a wrong way
  * Inability to reorder a downloadable product
  * ACL tables aliases interference with other table aliases
* Several tests are made incomplete temporary, appropriate bugs to be fixed in the nearest future
Update as of 7/3/2012
* Refactored backend (admin) menu generation:
  * Menu is separated from `adminhtml.xml` files into `menu.xml` files
  * Rendering menu became responsibility of `Mage_Backend` instead of `Mage_Adminhtml` module
  * Implemented XML-Schema for `menu.xml`
  * Actions with menu items defined in schema: add, remove, move, update, change parent and position
* Refactored customers import feature. New ability to provide import data in 3 files: master file (key customer information) + address file (customer id + address info) + financial file (customer id + reward points & store credit)
* Optimized memory consumption in integration tests:
  * Found and eliminated memory leaks in `Mage_Core_Model_App_Area`, `Mage_Core_Model_Layout`
  * Manually unset objects from PHPUnit test case object in `tearDown()` in integration tests. Garbage collector didn't purge them because of these references
  * Disabled running `integrity` test suite by default in integration tests
* Improvements in visual design editor JavaScript:
  * eliminated dependency of code on HTML-literals, reduced code coupling between templates and JavaScript files
  * implemented blocking unwanted JavaScript activity in visual design editor mode
* Various fixes in UX, code stability, modularity
* GitHub requests:
  * [#23](https://github.com/magento/magento2/pull/23) -- added `Mage_Customer_Block_Account_Navigation::removeLink()`
Update as of 7/19/2012
* Implemented inheritance of locales. Inheritance is declared in `app/locale/<locale_name>/config.xml`
* Moved declaration of modules from `app/etc/modules/<module>.xml` to `app/code/<pool>/<namespace>/<module>/config.xml`
* Implemented ability to match URLs in format `protocol://base_url/area/module/controller/action` (as opposite to only `module/controller/action`), utilized this feature in backend (admin) area
* Added product attribute set "Minimal Attributes", which consists of required system attributes only
* Improved customers import:
  * Implemented "Delete" behavior for importing customers, customer addresses and financial data
  * Implemented "Custom" behavior, which allows to specify behavior for each item directly from the imported file
* Updated performance tests:
  * Enabled Product View, Category View, Add to Cart, Quick Search and Advanced Search scenarios
  * Added ability to specify configuration parameters per scenario and refactored bootstrap of performance tests
* Implemented `mage.js` for base JavaScript initialization of the application
* Implemented new JS translation mechanism. JavaScript translations are loaded by locale code stored in cookies
* Implemented unit tests for JavaScript widgets in Visual Design Editor
* Added jQuery plugins: Cookie, Metadata, Validation, Head JS
* Fixed issues:
  * Impossible to add configurable product to the cart
  * Impossible to apply Shopping Cart Price Rule with any conditions to cart with simple and virtual product
  * Memory leak in email templates
  * Impossible to place order with Multiple Addresses using 3D Secure
  * Required product attributes are not exported
  * "Forgot Your Password" link on checkout page inactive after captcha reloading
  * Validation of "Number of Symbols" field in Captcha configuration doesn't work
  * Other small fixes
* GitHub requests:
  * [#37](https://github.com/magento/magento2/pull/37) -- fixed particular case of "HEADERS ALREADY SENT" error in WYSIWYG thumbnail
  * [#39](https://github.com/magento/magento2/pull/39) -- added `composer.json`
  * [#40](https://github.com/magento/magento2/pull/40) -- fixed generation of "secret key" in backend URLs to honor `_forward` in controllers
Update as of 7/26/2012
* Implemented Magento Validator library in order to have clear solid mechanism and formal rules of input data validation
* Moved translations to module directories, so that it is much more convenient to manage module resources
* Updated inline translation mechanism to support locales inheritance
* Implemented ability to navigate through pending reviews with Prev/Next buttons, no need to switch to grid and back
* Fixed issues:
  * Unable to use shell-installer after changes in Backend area routing process
  * Incorrect redirect after entering wrong captcha on the "Forgot your user name or password?" backend page
  * Translation is absent for several strings in Sales module `guest/form.phtml` template
  * Exception during installation process, when `var` directory is not empty
  * Node `modules` is merged to all modules' config XML-files, although it must be merged to `config.xml` only
* GitHub requests:
  * [#39](https://github.com/magento/magento2/pull/39) -- added `composer.json`, which was announced at previous update, but mistakenly omitted from publishing
Update as of 8/1/2012
* Refactored ACL for the backend
  * ACL resources
    * Strict configuration format, validated by XSD schema
    * ACL configuration relocation from `app/code/<pool>/<namespace>/<module>/etc/adminhtml.xml` to `app/code/<pool>/<namespace>/<module>/etc/adminhtml/acl.xml`
    * Renamed ACL resource identifiers according to the format `<namespace>_<module>::<resource>` throughout the system
      * Backend menu configuration requires to specify ACL resource identifier in the new format
      * Explicit declaration of ACL resources in `app/code/<pool>/<namespace>/<module>/etc/system.xml` instead of implicit relation by XPath
    * Migration tool `dev/tools/migration/acl.php` to convert ACL configuration from 1.x to 2.x
  * Declaration of ACL resource/role/rule loaders through the area configuration
    * Module `Mage_Backend` declares loader for ACL resources in backend area
    * Module `Mage_User` declares loaders for ACL roles and rules (relations between roles and resources) in backend area
  * Implemented integrity and legacy tests for ACL
* Fixed issues:
  * Losing qty and visibility information when importing products
  * Impossibility to reload captcha on backend
  * Temporary excluded from execution integration test `Mage_Review_Model_Resource_Review_Product_CollectionTest::testGetResultingIds()` and corresponding fixture script, which cause occasional `segmentation fault` (exit code 139)
* Refactored methods with high cyclomatic complexity:
  * `Mage_Adminhtml_Block_System_Store_Edit_Form::_prepareForm()`
  * `Mage_Adminhtml_Block_System_Config_Form::initForm()`
  * `Mage_Adminhtml_Block_System_Config_Form::initFields()`
* GitHub requests:
  * [#32](https://github.com/magento/magento2/pull/32) -- fixed declaration of localization CSV files
  * [#35](https://github.com/magento/magento2/issues/35) -- removed non-used `Mage_Core_Block_Flush` block
  * [#41](https://github.com/magento/magento2/pull/41) -- implemented ability to extends `app/etc/local.xml` by specifying additional config file via `MAGE_LOCAL_CONFIG` environment variable
Update as of 8/2/2012
* Refactored ACL for the backend
  * ACL resources
    * Strict configuration format, validated by XSD schema
    * ACL configuration relocation from `app/code/<pool>/<namespace>/<module>/etc/adminhtml.xml` to `app/code/<pool>/<namespace>/<module>/etc/adminhtml/acl.xml`
    * Renamed ACL resource identifiers according to the format `<namespace>_<module>::<resource>` throughout the system
      * Backend menu configuration requires to specify ACL resource identifier in the new format
      * Explicit declaration of ACL resources in `app/code/<pool>/<namespace>/<module>/etc/system.xml` instead of implicit relation by XPath
    * Migration tool `dev/tools/migration/acl.php` to convert ACL configuration from 1.x to 2.x
  * Declaration of ACL resource/role/rule loaders through the area configuration
    * Module `Mage_Backend` declares loader for ACL resources in backend area
    * Module `Mage_User` declares loaders for ACL roles and rules (relations between roles and resources) in backend area
  * Implemented integrity and legacy tests for ACL
* Fixed issues:
  * Losing qty and visibility information when importing products
  * Impossibility to reload captcha on backend
  * Temporary excluded from execution integration test `Mage_Review_Model_Resource_Review_Product_CollectionTest::testGetResultingIds()` and corresponding fixture script, which cause occasional `segmentation fault` (exit code 139)
* Refactored methods with high cyclomatic complexity:
  * `Mage_Adminhtml_Block_System_Store_Edit_Form::_prepareForm()`
  * `Mage_Adminhtml_Block_System_Config_Form::initForm()`
  * `Mage_Adminhtml_Block_System_Config_Form::initFields()`
* GitHub requests:
  * [#32](https://github.com/magento/magento2/pull/32) -- fixed declaration of localization CSV files
  * [#35](https://github.com/magento/magento2/issues/35) -- removed non-used `Mage_Core_Block_Flush` block
  * [#41](https://github.com/magento/magento2/pull/41) -- implemented ability to extends `app/etc/local.xml` by specifying additional config file via `MAGE_LOCAL_CONFIG` environment variable