Ah, the only thing I ever wanted from Longhorn, WinFS is in beta. Tom Rizo talks about how it leaked early, which might explain why the installer is there but attempting to get the developer documentation link throws an error. The WinFS blog is also rather empty. 33 minutes till the installer is on my machine, now I just need to wait for the documentation to be published.

[20:03] Huh, now the seperate documentation download has vanished from MSDN. So I think it's safe to assume the CHM file is actually in the SDK download. Now, does anyone know if it's going to have the same dependency problems as VS2005 and SQL, or doesn't it need a particular version of the .net framework?

[20:20] Ah there we go; "You also need to uninstall Microsoft Visual Studio 2005 and Microsoft .NET Framework 2.0 releases that are earlier than Beta 2".