I know it's a bit late but better late than never... right?
Just surfing and found the Vista blog post about Windows 7. Seems they are going to keep the code name Windows 7 as the official release name. They say that as they don't release a new OS each year the whole date thing, 95, 98 etc don't make sense and coming up with 'an all-new "aspirational" name does not do justice to what we are trying to achieve'
You can read the full blog post
here
