From AnandTech:
“Rumors are swirling that the release date for Microsoft’s Windows Vista operating system has been pegged at Decemember 7th, 2006:
The report, which claims to be based on “very recent internal Microsoft documentation”, said the first release candidate of the operating system, RC0, will appear on 19 April next year, with the second release candidate due on 28 June 2006.
Vista will then be released to manufacturing on 9 August. The first beta of Vista has already made it to testers, after making its appearance in late July.”