Why isn't anyone taking into consideration that:
With an MBA you *have* to tow the charger along as 4 hour battery doesn't cut it. That's an extra ~1.75 lbs.
With a 13" MBP it holds 6 maybe 7 hours easy of battery, so you can leave the charger behind. So that's like ~.5 lb less than MBA/charger.
The MBA charger is ~1.75 lbs??
For travel your logic doesn't work (for me anyway). I bought a MB 13 Alu when it first came out. It's a great machine. But, it's nearly 1.5-2x the weight of my previous Lenovo. And yes, it definitely does make a noticeable difference.
I too am waiting for the next rev of the MBA. I'd like to get more memory for VMs and a slightly larger SSD. For me though, it's all about the carry weight at the end of the day...