It's a one-time online authentication when you install the game, and then the only other time it checks your game is if/when you download any DLC.
Other than that, the only DRM is the limitations on installations.
It's stupid, but I also think it's stupid if you're ditching a game just because of this.
LEFT4DEAD411.COM
Bet with disolitude: Left4Dead will have a higher Metacritic rating than Project Origin, 3 months after the second game's release. (hasn't been 3 months but it looks like I won :-p )