GameStar.de have posted a new Grand Prix 3 screenshot showing a new style of mirror system actually where it is on the wheel instead of the actual mirrors which are now see-through. It is also a wet weather screenshot demonstrating the dry line and also the standing water reflection effect!
You can see it on the screenshots page!
Update: Christopher Boas has told me that GameStar have now said that there was a 'screen-grab' error, and there is no mirror system like that after all!!