If you can't wait till Friday the 28th to get your Sega Rally goodness, then head over to Live Marketplace and download a demo of the game.
The demo weighs in at just under 700MB features two tracks, Canyon 2 and Tropical 2, as well as two cars, the Mitsubishi Evo IX FQ3 and the Subaru Impreza STi Spec C type RA.