* Deleted DatabaseMysql.php, no longer necessary, database classes are autoloaded.
* Moved wfGetMimeMagic() to MimeMagic::singleton()
* Fixed a couple of __CLASS__.'::'.__FUNCTION__ things.
* Made lines from initialiseMessages() appear as list items during installation
* Moved the bulk of the localisation data from the Language*.php files to the Messages*.php files. Deleted most of the Languages*.php files.
* Introduced "stub global" framework to provide deferred initialisation of core modules.
* Removed placeholder values for $wgTitle and $wgArticle, these variables will now be null during the initialisation process, until they are set by index.php or another entry point.
* Added DBA cache type, for BDB-style caches.
* Removed custom date format functions, replacing them with a format string in the style of PHP's date(). Used string identifiers instead of integer identifiers, in both the language files and user preferences. Migration should be transparent in most cases.
* Simplified the initialisation API for LoadBalancer objects.
* Removed the broken altencoding feature.
* Moved default user options and toggles from Language to User. Language objects are still able to define default preference overrides and extra user toggles, via a slightly different interface.
* Don't include the date option in the parser cache rendering hash unless $wgUseDynamicDates is enabled.
* Merged LanguageUtf8 with Language. Removed LanguageUtf8.php.
* Removed inclusion of language files from the bottom of Language.php. This is now consistently done from Language::factory().
* Add the name of the executing maintenance script to the debug log. Start the profiler during maintenance scripts.
* Added "serialized" directory, for storing precompiled data in serialized form.
* Introduced doEdit(), a simplified editing API. Rewrote updateArticle() and insertNewArticle() to call doEdit() and marked them deprecated. Callers should be updated to use doEdit() at a later date.
* Replaced $fname with __METHOD__
* Removed some unused member variables
* Fixed cache purging on null edit, hopefully it should work the same as action=purge now.
* Fixed doRedirect() callers, minor bug introduced with HTMLCacheUpdate.