I think if you wait that you'll still do alright in the end. BMW is staying silent to get rid of 2011's in the dealerships. When the official 2012's are a reality then BMW will try to unload the remaining 2011's first.

If you are prepared to wait up to 6 months I am sure you'll get either the latest greatest vehicle or a great deal on a 2011. You might even decide to buy a different model of BMW depending on the changes made on the 2012 models...