You are kidding. it skipped it!
SP1 may not even be on Windows Update yet. They were targeting "November". Remember we're testing an early pre-release of a brand new app. By the time it comes out of Beta and is released, SP1 should have been automatically downloaded by anyone who needs it.
I forgot Microsoft is like DDI and slow to get things done. 
If I'm not mistaken, the .NET framework 3.5 is an optional update, since not all PCs need it.
Adding a Service Pack or similar release to Automatic Updates usually happens some time after the initial release. Service Packs have the tendency to change a lot of stuff and create unexpected side effects, and this gives administrators world-wide the chance to see if such side effects occur and either inform Microsoft (if it's serious enough) or implement their own fixed for this. If all Windows PCs automatically update, you risk problems. Of course, this still assumes that Admins stay in touch with the service packs and similar fixes, but that's kinda his job.
That might be, too. IIRC, Vista ships with .NET 3.0 build in, not 3.5.
congorats!
