I would rather get a mackbook. For a THOUSAND DOLLARS LESS you get the top of the line macbook with the same screen size, and plus you get more usb ports, actually have firewire, has a damn superdrive. 186 gb more drive space, stereo headphones, and the video out hookups, plus 2 more gigs of ram. plus the fact its a better processor (2.4 vs. 1.8). And at least you can replace the battery, hard drive, expand the ram and such all yourself.
I'm getting around 4 hours on macbook and thats still pretty impressive compared to most of the laptops on the market
logic says the higher the price the better the product. but in the mba case, the price is just all for looks. No way would I spend a thousand dollars more because I want to save .003 inches in my bag.