I'm waiting till it's offically released before I start anything with vB3. I've looked over it and it's okay, but I'd rather wait till all the bugs and the final style is done.
As for templating it looks a lot different, and maybe harder? than previously as they have all the IF statements etc in there. Plus as it is now the templates looks crap. Granted I've only spent 10 minutes in total looking over them.