Well if you're ok with chunkier and you really need all those features take a look at this: Sony Vaio UX
Weighs about 1.1 pounds, gets 2.5-3 hours battery life, and costs $2500. I've had a chance to play with one on numerous occasions. After you get over the "this is a real computer!" wow-factor, you quickly realize how clunky, fragile and heavy it feels. It really is a matter of what you need in a portable computer.
I'm sure once the Intel MIDs start showing up, Linux-based distros with more finger-friendly UIs will be a dime a dozen.

Side note on "re-flashing": I really don't know how Nokia managed to miss the boat so impressively. The Angstrom guys (who do a distro for the Zaurus) have had the upgrade-in-place problem nailed for quite a while. With Debian as a base OS this should not be that hard to solve and should be a high priority. *Shakes head and shrugs*