Unfortunately for enthusiasts, this is an unlikely scenario and here's why. The transmissions to be built in St. Catharines will be front-wheel drive units. GM probably chose to build them there in part because of the proximity to Oshawa so they will probably be used there. All recent indications from GM are that the previously planned RWD replacement for the Impala built at Oshawa will never happen. Instead, an updated front wheel drive model with the 6-speed will be assembled. The 2010-11 timing of the launches does correspond with the second generation GM mild hybrid system which could be used with the 6-speed rather than the far more expensive two-mode system. Given the market and CAFE realities, a direct injected, turbo four cylinder, front wheel drive Impala with a second generation mild hybrid is probably what we'll see from Oshawa in early 2011.
[Sources: Industry Canada, Globe and Mail, GM Inside News]