Is ~22 mpg what you're getting when you're trying to shift before boost comes on or just whenever?
That is conservative driving, staying out of boost. I've never driven, constantly getting on the gas, but it'll drop to 19-20 mpg if I get on it every now and then
I keep hearing they're planning on bringing back the 2.0L to the 2013 WRX with a little more hp like ~5 and lighter perhaps. Though like all refreshes the new engine might have some bugs for the first year. That's my main concern about waiting till 2013.
I've read 2.0L, 1.6L, and everywhere in between. I think this depends more than anything on what they are planning as far as WRC goes. It would be nice to use the 2.0L from the 2012 Impreza, but to compete in WRC the cars must have 1.6L engines. Either way, I would think they'll do what is necessary to keep the performance the same or better in the future, i.e. more boost or lower weight.