The multiplayer is complete rubbish. The few games I played with a friend were absolutelty horrible. Despite the lag, one game seemed to glitch out. Everyone had no health, and yet everyone was invincible...it only fixed itself when the game time ran out and another round started. I ranted about it for a few hours to my boyfriend, thats how much it crapped out. It kinda seems like multiplayer was an afterthought - not a very good one, either.
That aside, I bought Tomb Raider for the single player and so far, it's pretty awesome! xD