Like most racers now, Need for Speed Hot Pursuit is really pushing the concept of social play. In fact, the new Autolog feature is basically an in-game social tool, keeping track of your friends' progress and allowing players to communicate back and forth.
One indirect way of player interaction is the challenge system, as the latest gameplay trailer demonstrates. When a buddy beats your existing score for a specific event, Autolog sends a message informing you of this one-upping. You may then accept the challenge and attempt to beat your friend's score.
If you succeed by beating his/her time, the Autolog will generate a taunting message ("Better luck next time.") and let you send it back to your friend -- ouch, burn. Snag the Hot Pursuit Limited Edition, and you will have a couple exclusive exotics to show off as well.