Call of Duty: Black Ops is one of the most played multiplayer shooters in the world right now, loitering below Counter-Strike and Modern Warfare 2. It's about to become even more popular. If you've been watching the Black Ops phenomenon from afar and find yourself wondering what the hell all the fuss is about, there's a free weekend kicking off later today. This will give anyone with a Steam account unlimited access to Call of Duty: Black Ops' multiplayer modes. The free weekend kicks off at 10AM PST / 6PM GMT, and you can get a head start by preloading the game on Steam now. Thanks to Evil Avatar for the heads up.