Infiniti, Audi and Volvo (along with Lotus, Kia, and all of Daimler-CHrysler I believe) were in the Sky Dome (err... Rogers Centre). The Audi display was great just like last year's with all the cars open and the batteries still connected (so you could play with all the bells n' whistles inside).
Did you miss Porsche, Honda, Acura, Mazda and Ford too? They were in the NOrth building.
