Keep in mind this is the first Motorsport title I play (coming from FH2). My impressions so far:
Graphics: sweet 60 fps, lively surroundings, realistic colors
Sound: very good
Drivatars: Excellent! They feel like real players, I didn't tone down their agression. They were pushing, capitalizing on your mistakes and make mistakes on their own. The only weak part was with the indy cars but I suspect they limited their vehicle's top speed.
Menus: really clean easy and fast
Physics are sooooo good. I noticed that snap oversteer which I am not sure on how realistic it is. Apart from that I loved everything! Night was good but wet racing was amazing!
The only big drawback is that I dont have a wheel yet :'(