Sources say that the RTM Escrow build of Windows Vista and Windows Server 2008 Service Pack 2 has been released to a group of internal testers. The build number of this pre RTM build is 6002.17506.090313-1730, compiled on March 13, 2009. The RTM build numbers are also finalised and would be 6002.17507.090319-1515 and 6002.17508.090320-1600
Windows Vista & Windows Server 2008 SP2 is expected to reach RTM in April 2009 and the final release announcement is likely to happen at the TechEd 2009 event scheduled for May 11-15, 2009 in Los Angeles. The release candidate version was made available to general public early this month.
News source: Neowin