The graphics did initially blow me away and it's definitely an awesome game, especially for a launch title. However I have to be honest, the more time I spend with the game the more corners I can see that were cut in order for Turn 10 to get it to run at 1080p/60fps.
1.) For one, there doesn't seem to be any type of anti-aliasing (jagged edge removal) implemented in the game.
2.) Also, some of the track side detail is 2D rendered such as the trees, which look like cardboard cut outs instead of fully rendered models.
3.) Other missing features are dynamic weather, night racing, day to night transitional races, etc. (every race seems to take place on a crystal clear day at 5:30 in the afternoon).
Now I realize I'm just picking nits here but as good as the game does look, I see a LOT of room for improvement! Hopefully by the time Forza 6 rolls around the developers will have a better handle on the hardware and can include some of those missing features without sacrificing framerate.