It's not suppose to come out until late 2006. Very late...
Microsoft hope they can get the final retail version out sooner. The new beta versions got the WinFS so it should be interesting to see how that turns out.
Final version of WinFS will be released a few months after Windows Vista ships. The RTM (Release to Manufacturing) of WinFS will include support for both Windows Vista and probably Windows XP. WinFS will be available as a download add-in for the .NET Compact Framework.
WinFS Beta 1 weighs in at 76MB.