I have to admit I'm surprised that both reviews (this and the Walt Mossburg one) state they were able to achieve well over Apple's claimed 10 hours batter life

I have to admit I'm surprised that both reviews (this and the Walt Mossburg one) state they were able to achieve well over Apple's claimed 10 hours batter life playing video, both reaching almost 12 hours. I'm surprised because a) that's one hell of a long time, and b) Apple, like everyone else I guess, tend to overstate battery life and reviewers seem to find it almost impossible to replicate the published claims.