Was playing with a little p4 HT Sony Vaio today.
Not much thicker than the Air - 4 USB ports, ethernet, built in bluetooth, wireless, a 160gb SATA HDD which was well protected.
Retail price a mere £1000. Bit of difference for features that better the Air. You won't be posting it in a jiffy bag, but then again, how many people will actually use that heavily marketed feature of the Air? I wouldn't trust the post to deliver a Panasonic Toughbook without doing the difficult and actually damaging it