I like the particle effect in the XMB wave, when you move the six axis the wave and particles shift about. The friends list looks good imo, more too look at. I like be able to go to the store icon in each section and being able to see whats new without going into the store as well. The dynamic themes are a nice touch as well I can't wait to see more of them...hopefully we'll be able to make them just as we can make regular themes too.
Overall though I thought there would be much more but I wonder if there is some things we've yet to see stuff like game integration of some sort, just something I was thinking about after watching the new MW2 multiplayer vid where it shows a gamer card like thing combined with the name of and avatar of the person you killed.