MacBook Air?

I am getting ready to buy a new laptop but I am unsure of what to get. I really like the new Macbook Air, but I don't know if it is really worth the price. I really like the fact that it's only 3lbs. considering I am a college student and will be lugging it around with me to cl. The other options I was looking at were the regular macbooks, macbook pro, or a sony vaio CR series. So basically what I need to know is, is if the price of the Macbook Air really justifies it's thin lightweight build? Any opinions?