If you're looking for an arcade racer on the PS3 look no further than
MotorStorm: Pacific Rift. MS:PR is an offroad racer in which you will drive a verity of different vehicles ranging from ATV's to monster trucks across a number of uniquely different courses that offer different routes of travel.
The graphics are overall very impressive, expect to find the odd low res texture if you stray to far off the beaten track but these are unnoticeable as you are whizzing passed them at high speeds thanks to the good use of motion blur. The game also bolsters a good heart thumping soundtrack, although this is pretty negligible as the game allows you to set up your own custom playlists using music off of your Playstation hard drive. The online aspect is very impressive as well allowing you to jump into a race of up to 12 people on any track with any vehicle with a relative lag free experience.
However the game isn't without its flaws, it has a pretty steep learning curve which may frustrate some people later on in the game, especially if they are looking to win a gold medal in every race, but the problem isn't so much about the learning curve but how the game handles it, rather than just your opponents getting faster around the track the AI get overly aggressive, more focused on destroying you than actually finishing the races themselves.
If you can look past these flaws you're left the best arcade racing experience you can get on the Playstation 3 right now, beating out other off-road racing games such as Pure and Baha with relative ease.