A new Windows 7 build 7057 has been leaked. It was compiled just 6 days back. It'll expire on 02/03/2010.
There are lots of changes in this new build. Some of them are as follows:
* The infamous UAC issue has been fixed. In previous Windows 7 builds when you changed the UAC level, Windows didn't show any prompt message. It was dangerous from security point of view as a malware can turn off UAC on a system easily.
* New user display Images
* New Wallpapers
* New Icons for few programs
* New login screen