I get about six out of my MBA, AirPort off since I don't browse with it. Brightness on automatic, same as the keyboard. That's the original model with a new OWC battery.

The new ones are advertised at 9 hours for the 11" and 12 hours for the 13", and from what I've heard those estimates are conservative...I know a friend got 14+ hours from his new 13". With the i7...