I'm also excited about the idea, but the implementation is really bad so far. Some services don't work at all, others work somehow but have implementation bugs, others just are very, very restricted... there's little to no customer care.... And the whole thing started in 2007!
It does seem well integrated, the Facebook widget looks very cool (for those who use Facebook). I fully intend to get this phone. I wish they had used omap3 and xenon flash. But then that would be making the perfect phone and Nokia never does that!