The last news i heard was 4th Quater. That was about the same time fo the Beta 1 release. But I think Wayne is correct with his 1st or 2nd Quater of 07 remark.
Dmon Vista's official date is 2007 with an unknown month right now. These is a final version that will be shipped in 2006 Q4 but it will not have WinFS, Search Features, The Game Shut down resource feature, and more I'm not sure on it all.
Last i herad they had announced that WinFS was not gonna be included with Vista. It was pushed back neyond "Codename Blackcomb" and they were not sure of the release of WinFS. Then they came out with the Beta to everones surprize. Since the Beta they havent announced what the plans are now. But i would double check all your sources on this one. I dont think WinFS is going to be included at all on Vista.