None of those games are racing games (the ones you mention last), Blur, Need for Speed and Project Gotham Racing are entirely different experiences than Forza and GT. Forza 2 moved four times as many units as the original, clearly indicating that people do care about racing games (yes, the 360 has a bigger installed base, the sales are still massive in comparison), even GT5 Prologue has moved has moved 3.80 million units and with downloads probably just shy of 5 million. Need for Speed are losing sales because they have lost sight of what the series once was and have effectively alienated their entire audience, PGR 4 moved nearly 2 million units and in fact more than PGR 3 (which was the first to appear on the 360).
Do you also think that Assassin's Creed, CoD etc will impact the sales if Wii Party or Dancing games on Kinect? Its the same thing really, people who love racing and cars aren't suddenly going to lay down their gamepad and disconnect the steering wheel in order to shoot people online. AC and Fallout aren't really multiplayer games at any rate and are useless to that point. If having more big games across genres at the same time impaired game sales in every case, you'd see nearly nothing moving in the fall when there are typically huge games coming out on parade, often several of them launched withing weeks of one another.
Reach being alone in stores (what about Starcraft II? Won't that steal all the Reach sales? Its one of the biggest multiplayer games ever where you can go online and gain rep? Or doesn't it work that way?) has no effect on the simple fact that games released this late into a console's lifecycle have a lot less impact than the flagship titles launched early on to spurr the sales momentum forward.
No one is denying that Reach will be huge, it will be by any measure, I do think, however, that assuming that racing as a genre is forgotten and that GT will have poor sales due to shooters and medieval themed action games launching in the same space is ludicrous.
PS: Racing games are getting more and more online capacity, there are even racing MMO's out there now and racing as a genre is on board the same boat that takes people online to play against friends and strangers, comparing scores and times. If anything, seeing all the various racing games with a mature theme being launched and selling fairly well today, I'd say that the racing genre is bigger than ever. You don't need to "draw the attention" of gamers who play Call of Duty and Assassin's Creed to sell a racing game, that notion is utterly absurd.
