People on the Steam forums are generally saying that Cities XL 2012 is pretty good... I'm a little wary though, because of the whole annual release cycle. There's a 2010, a 2011, and now a 2012 version of the game.
It's been a while since I've really gotten into a city builder though... if it's as high-quality as people say it is, I might actually buy this one. :hmm: