Well, they announced Resistance 3 and I've gone back to playing Resistance 2 again. This game never gets old and it's just as fun now as it was the first time I opened up the box. This is the best co-op game you'll ever play. The only other one that compares is the old Delta Force games on the PC.
This game has a good story and I haven't even played the first game yet. I'm going to have to pick that up and run through it so I know the story from the beginning. Kinda like how I'm doing FEAR and FEAR 2 right now. Beat the first one and on the 2 one now. Only I'll have to go in reverse order since I picked up Resistance 2 first.
The co-op mode is done right though. You have 3 classes and you need all 3 in the game working together to make it work. If not, you'll die and never finish a mission. You have a Gunner, Assault, and Medic. You can play with up to 8 players. If you find a good team and coordinate decently, it will help you get through the missions easier. Each class can level up and get better stuff the higher level they get. Level 30 is when you stop getting things. However, their is a trophy for hitting level 50, so getting to 20 might mean playing on a higher difficulty for more experience to get their faster. So everyone needs to be at a high level to try superhuman mode.
The single player won't disappoint you either. It has a great story involved with it and it has some hard sections on it. I've beat it on easy and hard so far. When I beat it on hard, I unlocked Super Human mode. I started it up but haven't played very far into it. I will go back and finish it though as their is a trophy for beating it on super human mode. Plus the campaign will help me rack up experience.
Speaking of experience, this game tracks all kinds of stuff and your experience from each type of mode you can play is tracked separately: single player, cooperative, and competitive. Then all 3 are combined for an overall rank of what your current status is in the game. Which at a certain level you get a trophy. It tracks all your kills, deaths, ratio, kills per weapon, and on. All kinds of stuff to look at in this game.
You definitely need to check out this game out if you own a PS3. You won't be disappointed.