Let me start by saying that this is is blatantly false; "Let me start by saying the only racing games to have critical sales success and good overall reception have been kart games.".
http://www.metacritic.com/game/playstation/gran-turismo 11 million sold
http://www.metacritic.com/game/playstation/gran-turismo-2 9.5 million sold
http://www.metacritic.com/game/playstation-2/gran-turismo-3-a-spec 15 million sold
http://www.metacritic.com/game/playstation-2/gran-turismo-4 11.5 million sold
http://www.metacritic.com/game/playstation-3/gran-turismo-5 10.9 million sold and counting
http://www.metacritic.com/game/xbox-360/forza-motorsport-2 4 million sold
http://www.metacritic.com/game/xbox-360/forza-motorsport-3 5.4 million sold
http://www.metacritic.com/game/xbox-360/forza-motorsport-4 4.2 million sold
http://www.metacritic.com/game/playstation-2/need-for-speed-underground 7.2 million sold
http://www.metacritic.com/game/playstation-3/need-for-speed-hot-pursuit 2.6 million sold
http://www.metacritic.com/game/playstation-2/need-for-speed-hot-pursuit-2 2.1 million sold
http://www.metacritic.com/game/playstation/need-for-speed-iii-hot-pursuit 3.1 million sold
How can you make the above statement? What exactly is your measure for sales success and good overall reception? For the record; the GT series is more highly reviewed on average than MK. I'm rorry, I just got so hung up on that opening line, it's grossly out place. I love me some Mario Kart (MK 64 is my fav to this day) but what you're saying makes no sense at all.
As for the motion control part; I don't really care for motion controls in racing, steering wheels are the way to go and I don't understand why anyone would think motion controls to be even an alternative in comparison. That said; Project Cars looks (and sounds) amazing, I hope Polyphony Digital are taking notes on the sound design and the addition of actual, physical twitch in the steering on different surfaces rather than one smooth, uniterrupted motion.
