One thing that has endeared me to Continental is that in 2007 they had a 25K award offering when they introduced their EWR-CGN service (now cancelled). So from any city in the US (I chose SEA), you could get a flight to CGN for 25K roundtrip, plus minimal taxes. To get this on topic for Air Canada, does AC ever do any such reduced mileage award offerings?

I haven't heard of Continental repeating that particular offer. But I'd be very tempted to choose a Star Alliance plan where I could count on that happening - not likely, I know. Upgrades are not particularly likely to me with any plan, so I really only care about the mileage award options.