Yes, I have that dell too, and it is powerful and heavy. But, for 1800, you can buy that, and the Asus Eee PC, so you can have them both, one very powerful machine, and one very portable one, for even cheaper than the Mac air.
The Eee is ugly, slow, and gimpped, so I wouldn't consider that a very good option. Unless all you do is surf the web and check email (and absolutely nothing else).
