I just picked up my brand new super white xB automatic a week ago and I noticed when I start it up and drive It doesnt like to shift into 4th gear until it warms up.  Driving on country roads at 55mph makes the engine rev around 3500 rpms for a few minutes until it finally shifts into 4th.  The dealer cant give me a strait answer if this is normal or not so I decided to come on here and ask fellow owners if this is normal.  Keep in mind I live in NY so its cold right now.  Thanks guys.

If you are leaving your car sit outside in the cold, this is normal.  The engine oil and transmission fluid has to warm up before allowing the car to shift into the final gear.   I have had this happen before on other cars when left outside in the cold.

It's normal.

Thanks for letting me know guys