I spoke to someone last night about this, the sti how it sits now will be based of the legacy chassis, 5dr, wider fender flares on the sti only, no wide fenders on the wrx, no more horsepower, just a different ecu tuning system, and avcs on intake and exhaust.
Also, they are supposedly going for a target wieght of 3100lbs.
I think it's shaping up to be pretty great. The shape is good, as long as they don't blow it on the details, this will be the best looking scooby yet. Rumor is, they're dropping the "Impreza" name and just going with WRX.
I just hope the STi comes in hatch form also. 330hp AWD hatch... my dream.