Yesterday (30-04-2009), Microsoft released the new RC1 build (7100) of Windows 7 and Windows Server 2008 R2 for Technet and MSDN subscribers. However general public release will be on 5th May 2009.
some of the improvements over the Beta version
-DirectAccess User Experience
-User Account Control
-AppLocker
-System Partition Size
-Network Troubleshooting
Download Links for Technet And MSDN Subscribers
Windows 7 Beta Expires on 1st August 2009 and Windows 7 RC will expire on 1st June 2010.
some useful links