As noted in the gallery titles, I wasn't able to actually find any Game Center games -- the button in the Game Center app shows nothing just yet. That's not a good sign for the first day. At least we can all get signed up and befriend each other. We'll keep an eye out for any games that get GC-enabled as soon as they're ready.
I plan on tinkering with the HDR photography quite a bit over the next few days. I could have used it during a short trip out of town this last weekend. It's also nice to see that the HD YouTube movie upload is working well. Be sure to let TUAW and our readers know what you like the most or least about this update by leaving a comment.