Hmmm, well I don't have an official list but I suppose Microsoft Windows Team has done some bug fixes in 10 or more builds. Many of those we will never know probably.
Here are some I know of based on my experience, information from other forums and other forms of research.
- Overall performance improvement with some re-work of the kernel (most likely to remove some diagnostic branches) in preparation for RC.
- Notepad.ini on startup (not really a bug)
- Fixed WEI assessment code, more accurate
- A newer build of IE8 optimized for 7068
- Memory management has been optimized a little
- Added and replaced numerous
drivers (which solves a lot of issues)
- Fixed some Windows Update issues
- Fixed some network discovery and wireless issues
- Fixed some AERO issues
- Improvements to Windows Media Center and media management
- Changed the TCP half open limit from 10 to 120
- Improved support for external storage devices (ie. thumbs, NAS, etc.)
- Improved startup and shutdown times
- Added support for MP4 files and standard codecs
- Enhanced printer support
- Fixed some issues when doing an update from earlier builds and Vista
- Fixed some dual display issues
- Homegroup was removed from Windows Explorer
There are many others and I'm sure someone will post some of them later. This build is definitely worth the install!!