Do you really think that a 12" screen is the only criteria to meeting the term "ultra portable"? I am pretty sure there are some "ultra portables" on the market that weigh the same as an Air, but can you really truly use a computer with an 11" screen? Really?
Yes, the Fujitsu P7010D has a 10.6" screen. Very usable.
People always walk by and ask, "Can you see those fonts?" At 1280 x 768, they were easy to see - very crisp. It also weighed 3.2 pounds.
The keyboard was also easy to use, once you got used to the ',', '.', and '/' keys being 2/3rds the width of the other keys. Again, people would ask how my fingers managed to fit on that keyboard.
For me though, a 32bit 1.1Ghz Pentium M is just too underpowered. I knew that going into the purchase (I had a P5020D from my previous employer and hated leaving it behind). I've gone 2 years with that purchase.
The other big drawback was the Intel 855GM video - it had a proprietary driver and mode that made it difficult to get Linux or OpenSolaris running
at the highest resolution.
And I'm pretty sure the HD was 4200RPM.
So, for me, performance wise, the Air will be a huge step up. And I'll get native terminal windows with a decent shell.
The drawback will be the size of the unit. But as I'm more concerned about
my back while running through an airport to make a connection, I'll accept
the trade-off.