That's funny, for me, there is no reason for an 11" MBA when there's an iPad available.
Certainly no knock against the new MBA, but for couch surfing, emailing, and movie watching, why on earth would one need a "real" keyboard, a flip up screen, and half the battery life?
Partly because this:
Because trolling forums by typing on an on-screen keyboard that hides half the display is crap.
Laptops remain much better ergonomically to type away. The Internet isn't a read-only medium.
And the battery life for surfing, listening to music, etc for the 11" Air is actually much better than what Apple states, according to the Anandtech review. It got over 7 hours. Plus for movie watching it has a better aspect ratio, better screen, and can....hey amazing.....rest on your lap without needing to be propped up.
Hell, with the App Store being available under OSX now, I see fewer and fewer use cases for the iPad. It's still useful as a "pull it out on a train or on the go to quickly look at a document" device. But even that has less justification with the smaller size, weight, and instant on/30 day sleep ability of the 11" Air. For couch surfing, movie watching, listening to music? I think the Air has it beat hands down.