Windows Server 2008 R2 RTM (Release to Manufacture) code is on track to be available to Microsoft partners sometime in the 2nd half of July.
Windows Server 2008 R2 will also be broadly available about the same time as the Windows 7 “General Availability” date of October 22, 2009.
For more information on these great new products check out these team blogs.
Windows Server Blog
Windows Team Blog