If the dealer can't (won't) fix it, ditch it now and go buy a pre-facelift one. Or one with a manual gearbox. This is old advice from Bimmerfest. Heck, I requested the mod to create a sticky just for this issue.

For all who aren't familar, the '07-early '08s have issues with the new 6-speed automatic. Not all of them are bad, but a sizeable portion are.