I played it too. Built a city till 250.000 people and then quit the game. Even if you say it runs on two threads it still drops the fps rate when zooming in even just a little. And I feel the need to mention that I'm not using shadows, traffic and other visual options that might drop the fps rate. Well... all in all, I have only one thing to say: Bad management leads to bankruptcy in the end. Good luck, Focus! Now I'm hoping that EA will make a new Sim City that is totally different than Deluxe.
If it doesn't have multi-core support I think this will be the last Cities XL that we'll see. A lot of people are waiting for CXL 2012 because they are expecting that multi-core support. If it doesn't have it, the obvious thing is that a lot of people won't buy it and it will be a failure on the market. At this point it is clear that they won't make another version.