I think it tries to look for the compeltely wrong things.
1) Apart from the fact that this medium didn't exist for the commodore it's a stupid argument. Again, if you need it so much, use remote disc or buy a drive.
2) Ethernet. Macbook Air is made for wireless usage, and an adapter is available for anyone who still lives in a sad wire world. Get a wlan router, man.
3) User replaceable battery. I think this is the stupidest argument of all. It's a typical geek statement because geeks will actually replace the battery themselves if they could. Normal consumers will send in even their macbooks or MBPs for replacement.
4) Keyboard. -_-
5) The last firewire device I have in my household besides a video camera is a 3G iPod with firewire. I mean, come on - this is not a powerhouse, it's supposed to be a sleek companion for the road.
I'd say people are not impressed because the MBA doesn't flaunt hrosepower, but has other distinguished features. Also, because of it's slightly high price people are put off by it because everyone expected a sub-notebook to be a sub-price-notebook as well.
Apple lacks a cheap notebook, and prayers weren't answered. But I'm getting this baby all the same.