It would be nice for BMW to allow tuning, but in such a way that they would catch all tunes with the improved software and just void the warranty...so people can choose if they want to tune and lose the warrany, or if they don't want to tune and keep the warranty
However, the BMW Performance chief said that they are working at a Power Kit for the N55 engine already. So this will probably be your first tune...if you are willing to pay