Update as of 10/11/2012
* Removed unused `Mage_DesignEditor_Model_History_Compact_Diff` class
* Fixes:
  * Incorrect title for Manage Products page
  * 'Element with ID 'wishlist_column_qty' already exists.' error on Manage Shopping Cart page
  * Incorrect redirect on "Print Shipping Labels" action, when shipment without shipping label selected
  * Error message is displayed twice, when restoring admin password with captcha enabled
  * Impossible to retrieve admin password, when captcha is enabled
Update as of 10/16/2012
* Introduced block arguments to the layout syntax:
  * Introduced the "object" block argument type to specify a grid data source
  * Introduced the "options" block argument type to accommodate key-value pairs
  * Introduced the "URL" block argument type to represent a URL with parameters
  * Introduced block argument updaters for the block arguments, which allow to customize the original grid arguments
  * Implemented extraction of translatable strings from block arguments in layout by the Translation Tool
* Declared the Customer Wishlist and Sales Order grids through the layout instead of the PHP classes
* Implemented the block `Mage_Backend_Block_Widget_Grid_Massaction` to encapsulate grid mass actions
* Moved grid columns and mass action management from the base grid `Mage_Backend_Block_Widget_Grid` to the `Mage_Backend_Block_Widget_Grid_Extended`
* Introduced the column set block `Mage_Backend_Block_Widget_Grid_ColumnSet` responsible for grouping columns in a grid
* Updated the grid rendering template to render a column set instead of rendering columns
* Eliminated dependency between the grid column block and parent blocks
* Denied the public access to the `pub/cron.php`
* Fixes:
  * Fixed the broken Billing Agreement View page
  * Fixed absence of the Default and Minimal attribute sets in the Manage Attribute Sets grid, if the total number of records is 22 and the view of 20 rows per page is chosen
  * Fixed typos on the Sales Order page
  * Fixed typos on the Sales Order's Packing Slips printed to PDF
  * Fixed preserving selected rows after searching in the Sales Order grid
  * Fixed "column not found" SQL error while sorting by the "Product Name" in the Catalog Pending Reviews grid
2.0.0.0-dev29
* Implemented and verified ability to upgrade DB from CE 1.7 (EE 1.12) to 2.x
* Replaced calendar UI component with jQuery calendar
* Restored back the public access to `pub/cron.php` entry point (in the previous patch it was denied by mistake)
* Fixed typo in label of "Catalog Search" index in UI
2.0.0.0-dev30
* Framework changes
  * Added dependency injection of framework capability
    * Adopted Zend\Di component of Zend Framework 2 library
    * Implemented object manager in Magento application
    * Refactored multiple base classes to dependency injection principle (dependencies are declared in constructor)
  * Themes/View
    * Implemented storing themes registry in database, basic CRUD of themes, automatic registration of themes in database from file system out of the box
    * Renamed `Mage_Core_Model_Layout_Update` into `Mage_Core_Model_Layout_Merge`, the former becomes an entity domain model. Similar changes with `Mage_Core_Model_Resource_Layout` -> `Mage_Core_Model_Resource_Layout_Update`, `Mage_Core_Model_Layout_Data` -> `Mage_Core_Model_Layout_Update`
* Performance tests
  * Improved indexers running script `dev/shell/indexer.php` to return appropriate exit code upon success/failure
  * Implemented running the same performance scenario file with different parameters
  * Slightly refactored framework class `Magento_Performance_Testsuite_Optimizer` for better visibility of algorithm
* Visual design editor
  * Added ability to remove elements in editor UI
  * Revised history of changes VDE toolbar and algorithm of "compacting" operations (moving, removing elements) as a layout update XML
  * Added selection of themes to VDE launcher page
* Refactored JavaScript of some UI elements to jQuery:
  * "Simple" and "configurable" product view pages
  * "Create Account" page
  * "Shopping Cart" page
  * CAPTCHA
  * Newsletter subscription
* Tax management UX improvements
  * Split Basic and Advanced Settings for Tax Rule Management UI
  * Moved the Import/Export functionality to Tax Rate page
  * Moved Tax menu to System from Sales
* Implemented the editable multiselect JavaScript component
* Added mentioning sitemap in `robots.txt` after generation
* Removed creation of DB backup in integration testing framework
* Fixed logic of order of loading ACL resources in backend
* Fixed JavaScript error during installation when one of files in `pub/media` is not writable
* Fixed structure of legacy test fixtures that allowed ambiguous keys in declaration
* Fixed inability to restore admin password when CAPTCHA is enabled
* Various minor UX fixes (labels, buttons, redirects, etc...)
* GitHub requests:
  * [#59](https://github.com/magento/magento2/issues/59) -- implemented handling of unexpected situations in admin/dashboard/tunnel action
  * [#66](https://github.com/magento/magento2/issues/66)
    * refactored ImageMagick adapter unit test to avoid system operation
    * simplified unit testing framework -- removed unused classes, simplified handling logic of directory `dev/tests/unit/tmp` and removed it from VCS
  * [#73](https://github.com/magento/magento2/pull/73), [#74](https://github.com/magento/magento2/pull/74) -- fixes in docblock tags
  * [#75](https://github.com/magento/magento2/pull/75), [#96](https://github.com/magento/magento2/pull/96) -- fixed translation module contexts in a few places
  * [#80](https://github.com/magento/magento2/issues/80) -- fixed some runtime errors in import/export module
  * [#81](https://github.com/magento/magento2/issues/81) -- removed usage of "remove" directive in places where it is overridden by setting root template anyway
  * [#87](https://github.com/magento/magento2/issues/87) -- changed paths of files to include from relative into absolute in `dev/shell/indexer.php` and `log.php`
  * [#88](https://github.com/magento/magento2/issues/88) -- provided comments for values that can be configured in `app/etc/local.xml` file
  * [#90](https://github.com/magento/magento2/issues/90) -- slightly optimized logic of implementation of loading configurable product attributes
2.0.0.0-dev31
* Themes:
  * Eliminated "skins" as a concept. Skins and themes are consolidated into one entity and now called just "themes"
  * New themes out of the box are named by their distinctive characteristic (thus, "default" is renamed to "demo")
  * Revised logic of handling "virtual" (which are present in database registry only, but not in the file system) VS "physical" themes
* Dependency injection:
  * Reduced memory leaks of integration tests caused by introduction of object manager
  * Added compiler for dependency injection definitions and ability to run Magento application with the compiled definitions
* `Mage_Adminhtml` breakdown:
  * Implemented XML-schema for system configuration form declaration files (`etc/system.xml` in each module), refactored them to comply with schema and relocated to `etc/adminhtml/system.xml`
  * Removed remnants of `Mage_Admin` module (replaced with `Mage_Backend` and others)
  * Removed multiple obsolete models in `Mage_Adminhtml` module -- replaced with more generic classes in `Mage_Backend` (less classes overall)
* Replaced `Magento_Test_TestCase_ObjectManagerAbstract` in unit testing framework by a helper in test suite
* Made the PHP coding standard test (`Php_LiveCodeTest`) treat white/black lists as `glob()` patterns and verify correctness of the actual patterns
* Consolidated `upload_max_filesize` logic into one helper
* Bug fixes:
  * Fatal error on Product Tags and Customers Tagged Product (on product editing page in backend)
  * Trailing space in date caused by new "date picker" JavaScript component
  * Impossibility to add product to an order in backend in IE8
  * Not picking a template on customer "Shopping Cart" page at the backend
  * "Use Default" checkbox is checked again after saving multiselect attribute config if option does not contain value
  * "Single Store Mode" UI fixes
  * Runtime error when previewing transactional email template
  * Incorrect redirect after applying filter in grids
  * Various asynchronous placement of profiler keys
  * Various fixes in Taxes backend UI
  * Various fixes in translation literals
2.0.0.0-dev32
* Improved product edit workflow:
  * Introduced Category Assignment control on "General" tab
  * Eliminated attribute preselection screen
  * Base image assignment control moved to "General" tab
  * Base inventory attributes controls displayed on "General" tab. Values of the attributes are synchronized between "General" and "Inventory" tabs
* Improved static code analysis tests to verify existence of paths specified in white/black lists
* Reduced memory usage by integration tests by automatic cleaning properties of test classes
* Added migration tool `dev/tools/migration/themes_view.php` for replacing old `{{skin}}` with new `{{view}}` placeholders
* Changed handling of exceptions, produced by non-existing view files, to not break whole page
* Removed empty locale files
* Bug fixes:
  * Page with tracking information absent, if shipping labels integration is used
  * Category is not displayed on frontend with "Use Flat Catalog Category" option enabled
  * Exception on "Coupons Usage Report" page after upgrade from Magento 1.x
  * Exception on "Most Viewed Products" page after upgrade from Magento 1.x
  * Quick search produces error, if searching for a product with an attribute that has "Use In Search Results Layered Navigation" option set to "Yes"
  * Exception on "Add/Edit Customer" page when Magento profiler with html output is enabled
  * Can't duplicate downloadable product with sample file attached
  * Product Type dropdown on "Add Product" page doesn't work in IE9
  * Various issues related to adding/editing product
2.0.0.0-dev33
* Improved Themes functionality to meet the following requirements:
  * Magento instance doesn’t crash in case there’re no themes at all
  * Features like selection of themes in system configuration, custom theme selection in Custom Design, CMS pages, Products and Categories can work without themes. They use base view files only.
  * Virtual themes work in the same way as the non-virtual (which are present in file system) though they additionally have inheritance property. Changes were made in theme switcher, in fallback mechanism, in widgets etc.
  * Non-virtual themes are being added to DB during installation
  * Application framework uses theme id as identifier instead of theme code
* Refactored a variety of report grids in backend (admin) to make them configurable through layout, rather than hard-coded.
* Removed obsolete modules:
  * `Mage_XmlConnect`
  * `Mage_Dataflow`
* Significantly changed Logging subsystem:
  * `Mage_Core_Model_Logger` class is responsible for logging
  * Changes are made to comply with DI paradigm
  * Custom logger in `Mage_Backend_Menu` subsystem is removed due to usage of regular one
* Changes made in autoload process
  * Fixed autoload to prevent `class_exists()` from causing fatal error
  * The `Magento_Autoload` library was divided into 2 classes: `Magento_Autoload_IncludePath` is responsible for loading from include path, `Magento_Autoload_ClassMap` from a class map. Stacked "class map" loader on top of "include path" loader in application bootstrap.
* Implemented new jQuery form widget. Its responsibility is to prepare form for submission (change form attributes if needed)
  * Replaced usage of different instances of `varienForm` with a new form widget (`productForm`, `categoryForm`, instances of type "onclick declaration", "as child component", "instantiation only")
  * Replaced prototype validation with jQuery analog
  * Additionally implemented form widget in different modules (CMS, Customer, Backend, Sitemap, DesignEditor, Tags, SystemEmail, Newsletters, ImportExport, Connect, Authorize.net)
* Minor improvements
  * Fixed css styles for validation messages in different parts of the system
  * Removed usage of `jquery-ui-1.8.21.custom.css`
  * Updated versions of jQuery and jQuery-UI on backend
  * Updated Magento trademark and copyright labels at the bottom of pages: changed legal entity name to X.Commerce, Inc, made translation engine pick them up
  * Improvements made in indexers to stabilize tests. Fixed wrong initialization order of indexers that sometimes caused failure of reindexing all at once
* Bugfixes:
  * Set correct order's data change state during voiding the order
  * Set translator to pick up status labels in drop-down in "Shopping cart price rule" admin grid
  * Fixed an issue in console installer that initialized application in such a way, that it could not load certain event area.
  * Fixed incorrect loader image source in backend during new tax rule creation
  * Fixed JS error in IE with creating products via floating toolbar
  * Fixed image save url during uploading product's images
  * Added permission check for editing shipping and billing addresses during viewing the order
  * Changed saving of order comments from backend. Comment is saved even without status change
  * Added additional validation into `quickCreateAction` of `Mage_Adminhtml_Catalog_ProductController` to prevent saving new product with any id using firebug
  * Fixed JS errors in Authorize.net Direct Post submodule
  * Fixed JS errors in split button on creating product
  * Fixed errors in poll's list template in backend