Add gitian-based, vagrant VM build system to enable building on any operating system platform.
Add a method for toggling bitcoin addresses between testnet and mainnet. Useful for hard-coded addresses which need to be used in either case.
Switch the type for representing coin balances from int64 to the GMP library's arbitrary-precision rational number type.
Add support for nVersion=2 reference-height transactions, which provides the necessary foundation for time-value adjusted currency.
Add enforced budgetary requirements - the ability to specify outputs which must be present in each coinbase or else validation fails.
Add new difficulty adjustment filter, which replaces the simple average over 2016 blocks with a faster-acting 144-tap Parks and McClellan FIR filter, and adjustments every 9 blocks with a gain of 0.1025 and limiter of 1.055.
Rebrand user-visible text and build process "bitcoin" -> "freicoin".
Update About dialog size and text
Change icons from blue -> green, to provide visual difference from Bitcoin.
Change network port, seed servers, and magic strings so as to avoid contact with the Bitcoin network.
Change Bitcoin genesis block for Freicoin on both mainnet and testnet, and update checkpoints.
Freicoin validation requirement: coinbase reference height must equal the block height.
Add Python script for calculating Freicoin demurrage parameters.
Demurrage rate of 4.89% for freicoins.
Add demurrage-compensating perpetual distribution.
Switch initial distribution to Freicoin's linearly-decreasing reward.
Add Foundation budgets, and associated portion of the initial distribution.
Fix Art Forz's time-traveller attack, where a 51% attack can change difficulty at will.
Enable new difficulty adjustment filter, as of block 28336.
Special, one-time adjustment of difficulty due to the "hash crash" of Apr/May 2013 which rushed the introduction of the new difficulty adjustment filter. The difficulty is adjusted back to the difficulty prior to most recent adjustment at that time.