Overall my wife and I love the X5, its classy, rides good, and gets decent mileage. Average 18 mpg in mixed driving, but 40 hp more would help move it better. On the Autobahn the faster you drive the better it runs and it gets the same 17 mpg at 110 as 80 mph! We keep the baby seat in the center, but it lacks the latch anchors so we have to stagger the two side seat anchoring points. Also, my biggest beef with the X5 is the factory running boards. While making it sportier they get in the way getting in/out. My poor wife gets dirty every time she puts the baby seat in. Lastly, the driver's seat always ends up in the wrong spot even w/memory seats, a few flaws that get irritating!
Power lift tailgate, sure footed in slippery conditions, moon roof with a solid cover. The parking assist is great with front and rear zones plus a rear view camera (although the camera shots aren't the greatest as others have said).
Factory running boards look good but are lousy and in dire need of a redesign. Technology package doesn't give you 6 disc in-dash CD changer (standard on much less $$ of cars out there!). The iPod interface quit working, but was replaced under warantee... I hope that proves to be the only problem!