just showed some pics on BB. As the Highline was never sold in USA, maybe some people are interested in to see that option.
http://www.bimmerboard.com/forums/posts/361206
http://www.bimmerboard.com/forums/posts/361259

Some more details:
the Highline has 2 alternators to power all the goodies, and it has a second aircon for the rear passengers.
http://bmwe32.masscom.net/johan/ihka/highline_2.jpg

http://bmwe32.masscom.net/johan/ihka/highline_1.jpg