I'm shopping for a new Macbook Air, and am amazed by Apple's claim that a battery charge lasts up to 12 hours. I would very much appreciate your real world field reports. How long is your MBA battery charge lasting? I'll be using a MBA to type text and work with videos, which I'm guessing are sort of best and worst case scenarios as far as power consumption goes. Your reports and speculation in either of these scenarios is most welcome. Thanks!