Apple claims the MacBook Air battery lasts 5 hours in normal use - normal, meaning with WiFi on, since this is the Air after all.
But Anandtech’s real-world test shows that this claim by Apple does not hold water. The best Anandtech was able to squeeze about the MacBook Air battery is 2.5 hours whil watching XviD Movies

The review concludes:

We’re still hard at work on the MacBook Air review, but this data was too important not to share right away. By now you’ve heard that under “normal” usage, the Air can only manage about 2.5 hours of battery life. That’s true and at the same time it isn’t. I touch on part of this in the review, but the MacBook Air isn’t designed to be your work notebook - no ultra portable is. It’s a notebook for a writer, for someone taking notes in class; it’s a second notebook, or a third system. As such, the typical usage model can be very different than your standard notebook.

To be fair, MBA lasted 4.27 hours on browsing the Web or playing MP3 music. I admit, this is good enough for me since I use my MacBook primarily to surf and blog. What I don’t understand is why watching a movie on the Air sucks the battery faster than having the WiFi on. Maybe the testers didn’t turn WiFi off.

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