It's funny how defensive people get when there's talk that their "Prized" MacBook Pro is about to be outdated soon.
But get used to IT that's just how Apple works... Their constantly updating, redesigning and releasing amazing products to feed the never-ending crave that consumers have.
So enjoy what you have now or wait and get whats next..... there's really no right or wrong way to do it.
If you're waiting, it only makes sense to wait for the 2012 model. IF there was a 2011 model, it wouldn't have the hardware changes that make it worth purchasing. That's simply the fact of the matter. Apple doesn't produce the physical hardware, Apple has NO say in when Ivy rolls out, or when the 28nm graphics cards come; 0 say.
If you want a thinner, but hotter and weaker MBA 15/17, be my guest.