BMW does something more useful with that map data

The new ActiveHybrid 3 series will feature a system that can predict the best time to charge its batteries. Since the navigation map data includes hill profiles, and the car knows the direction you’re headed this means fuel efficiency.
Say you’re about to go uphill for a while and then descend back down hill. Your car will let you use more of your battery instead of precious fossil fuel while climbing knowing it can recharge on the way down. Pretty sweet eh?
ActiveHybrid 3 will go on sale this fall. Expect to get about 37mpg on the highway before navigation