I just wanted to throw my two cents in here..
I put in a preorder for the Macbook Air the second the store came online after the keynote. Due to this, I've had mine since thursday, so I've gotten a decent amount of time to play around with it and use it in day-to-day settings. On a side note, when I first powered this thing on, it got freking HOT!! A fan started blasting very loud, and I was pretty upset.."is THIS the air?" I thought? Well, I turned the machine off and let it charge up - since then, I've not once heard the fan, and the unit has been much cooler (though still gets a bit warm).
Let me first say that the battery life is quite good. I've been running BT and WiFi simultaneously in "better energy savings" mode whilst on the battery and have observed a little over 4 hours of usage - that's while actively browsing the web, having multiple apps open, and listening to music..not bad, if you ask me.
I did purchase the usb superdrive and the usb ethernet as a "just in case" precaution, but have yet to use the dvd. The OP makes a good point - though I was weary at first (heck, I almost cancelled my order after learning there was no dvd drive), the simple truth is that I hardly ever use the dvd drive in my laptop these days. Most of the time when I'm out, I use thumbdrives, rarely a dvd/cd. As far as ethernet, the dongle is so small, the cable might as well be plugging directly into my machine as I can't tell a difference.
Another thing people have mentioned, is the fact the unit has only one USB port and no firewire. I can't comment on the loss of Firewire, really, as I have no firewire devices. However the single USB port is ample, seeing as how BT and WiFi can handle just about everything else these days (wireless printer, wireless mouse, wireless keyboard, wireless storage..). Something to keep in mind is, the laptop was obviously built around people utilizing wireless technologies - hence the name - AIR. Apple wants you to be using airwaves, not cables. So far so good as far as I'm concerned!
The display is phenominal, the keyboard is great, and god I LOVE the new touchpad!! I can't say enough about the touchpad - it's fantastic. I didn't think it would be anything more than a gimmick at first, but I really appreciate it now that I have it.
The system itself is plenty "snappy" with the base model 1.6ghz cpu. I was a bit worried about the 80gb 4500rpm drive being too slow, however it performs admirably - and I appreciate the added space over the SSD. I really don't believe I'd recommend anyone getting the SSD option after seeing how well the 4500rpm does perform. The loss of space and the loss of money just doesn't add up to me..
After all is said and done, my only complaint about this laptop is hard disk space. 80gb is just too little. I plan to augment this capacity issue with some 16 or 32gb thumb drives that I'll carry around with me, but it just seems Apple could've thrown us a bone and included a larger disk..maybe they didn't want to make the SSD seem completely ludicrous..
Anyway..I LOVE my MacBook Air, and I'm sure just about anyone will..it's speedy, it's sexy, and it's freking sturdy (NO flexing at all). I wouldn't recommend this to someone who doesn't already have another computer, however.