I am still waiting for a 13" Macbook Air with an Apple ARM processor, 10 hours of battery, RAM upgradeable to 8GB and 512gb SSD drive by default, for less than $1500. Hopefully it'll be out in a year. Maybe two.

Lugging around my Core2Duo MBP weighing at over 2kg does get quite tiring. :( I need its battery life though.