I drive a new 2012 X5 35d and have noticed a similar sound from the driver's door when going over bumps, etc. A squeak or creak - my wife wouldn't believe the car made that sound initially but now she is convinced. The dealer has looked at it once last weekend, said they heard the same sound, and lubricated "something". I didn't have time to get into details. Needless to say, the sound was there on the drive home. We'll revisit.
They did apply the felt tape to the B-pillars and the clicking everyone talks about is gone. My SA also knew of the problem as soon as I started talking about it.
My X5 was part of the recall for improper fitting steering gear or gasket. It didn't have to be fixed per my SA. Not fun to get a call and recall notice on a car with 400 miles on it though.