Chris Brumme states:
Incidentally, I still can t believe that we picked WinFX to describe the extended managed frameworks and WinFS to describe the new storage system. One of those names has got to go.
Yep. WinFS is still considered a code name, while WinFX is the name they think they want to ship with. John Montgomery has been conducting a poll looking for naming suggestions. It will be interesting to see if he comes up with anything.