I owned a Rev A MBA and loved it to death. I only sold it to get the unibody MacBook because I burn quite a bit of media for clients after sales presentations and find the MacBook's built in supedrive more convenient.
With that in mind, I have to say I've been considering a move back to the Air quite a bit lately as I have moved over to USB thumb drives instead of optical media for my clients so the built in superdrive isn't as important.
After much thought on what we may see come down the road in the future for the Air I can only guess, and it is my unfortunate feeling that the Air is not going to see 4Gb of RAM or much more than the 128Gb SSD drive. And believe me, I would love to be wrong here, but I believe the positioning of the Air is to be exactly what it it right now: a more than capable, single OS instance-at-a-time, web browsing, email crunching, full keyboard having joy of a portable computer.
Why would Apple build much more in the way of resources into the Air anyway? Think about it for a second. They have never positioned the Air to be powerful, just portable. And portable it is (in spades!). For a more powerful computing experience I believe they would like to push their customers to the more apt MacBook Pro line which is actually not that much bigger than the Air anyway (I took
some comparison pics here when I had them both for a few days) and much more capable when the need for power arises on the go.
Maybe I'm just being a pessimist,
and believe me when I say I hope I'm wrong, but it is my feeling that the Air will continue along generally the way it is for a while with regards to its computing power. They certainly would be well-served to update things like the chassis, the screen and the trackpad, but overall I'd bet a small sum of iTunes gift card credits that the Air is about as powerful as it is going to get.
Did I mention that I hope I'm wrong yet??
**really missing his Air and will probably still buy a Rev C anyway soon...just needed to get that off his chest**