I think we started to see a huge decline in co-op when games like Quake 3 and Counter-Strike came out, and did really well. Sadly, there has been a lack of co-op in many games, and I really do sit there and ask myself why they don't put this option for multiplayer more often. I do, however, notice a huge incline in upcoming games that are noted to have this option. I think we are going to start noticing a lot more games in the near future that deal more on this aspect, than some sort of deathmatch. A lot of companies wanted to go with having a "team against team" type of multiplayer in the past few years, and have been to worried about making it new and fresh.. Like making new styles, examples like Capture the Flag and King of the Hill. It's always nice to see they add on and create new styles, but I think it has been a shame they left the 2-4 player co-op out lately.