I'm surprised by the number of people that believe theres still going to be something called the MacBook Air.
The new rMB is the MacBook Air. It's essentially thinking hey, they're going to make an iPad and an iPad Air every year.
As I said on another thread, the 12" MacBook was Apple's vision of the future of computing. In the near future, the MacBook will feature wireless charging and in time most computers will act as a dumb terminal as more and more apps become web-based (hence the reason why such a machine will never require a beefy CPU). The MacBook will serve a purpose for the masses - eventually. It's not quite time yet, but I wouldn't be surprised to see a 14/15" version appear and for the MacBook to co-exist alongside the Air & Pro line for at least another year or two.