8 human players, each human players has 3ai team mates to control.
Yeh, the game needs a few patches - but so do nearly all games upon launch. Especially such large and ambitious ones like this.
The single player missions are good. You get dropped in to your starting point, you are then gave 1 objective at a time and it's position on the map, you can get there anyway you want and usually however you want. There are usually PLA (the enemy) checkpoints along the way, and patrols you need to watch out for. You can go stealthy and sneak past them all, or shoot every enemy you see. The AI are generally very good, they don't have super vision like ArmA2 and FarCry 2 (if it's dark, they won't see you till you're within 100meters or less if you have good cover) and if you use a silenced weapon and manage to kill one in a single hit, it doesn't necessarily mean the AI know where you are. usually they sound the alarm and go on a hunt for you.
The single player experience is really good, from how the weapons react, to the awesome FLIR scopes on some of the guns (hot things are white, so when you shoot someone from a distance away, you see the spray of blood before they hit the ground
)
The game even calculates the speed of sound and shockwaves, you will see artillery and gun fire before you hear and feel it. The sensation of bullets wizzing by and hitting the ground around you is very very good, some of the best I've seen - it really makes you take cover. Especially as even an arm shot can kill if you don't attend to it.