I hope they release a wheel and pedals for all the non-wheel and pedals owners out there, but I doubt it. My guess is that MS discontinued the 360 wireless wheel and pedals in 2007 because it was not making money for them. The vast majority of folks that play racing games on their 360 use a controller, not a wheel. I only started using a wheel a few years ago, after MS reduced the price of the wireless wheel and pedals to $99.99. Today, I spend 95% of my gaming time playing racing games, but that is not the typical 360 owner that they have to market to.
As an aside, I saw a video this morning on YouTube that shows some Forza 4 footage. The guy is playing it on a MS Xbox 360 wireless racing wheel, which was discontinued years ago.