Adam and I finally beat the co-op on Portal 2 so I feel like I can discuss the game. First, the good things. Co-op works pretty well, at least splitscreen, and it's fun. Sometimes it was frustrating that I wasn't always the one to find the solution to a puzzle, but that's the tradeoff when you play with someone as smart as you. It was a relief to be a robot and not be afraid of dying; funny how much that affects my game experience. I think there's room for more co-op puzzle games in the world.
Of course Portal 2 is very fun, and the puzzles are just hard enough that you can keep feeling smart (and that takes some subtle scaffolding, let me tell you). The only parts I struggled were the "guess where to place the portal" puzzles, and I don't feel bad about getting stuck there. This is definitely a great game, but it 's not as narratively tight as Portal (see that discussion over at the Brainy Gamer). It's also not as experimental as Portal (full disclosure: still working on my thesis about Portal and House of Leaves).
Portal's narrative is exciting to me as a literature student because Chell doesn't win, but you as the player "beat" the game (and you get your cake). Meanwhile, GLaDOS sings about how she's definitely still alive. This overt acknowledgement that we don't actually care about the protagonists, but it's our experience as players that should be awesome, feels new and exciting (or post-modern, take your pick). Are there other games where the protagonist loses while you the player wins? I can't really think of any, but please comment if you think of one.
Portal 2 went for a happy ending for almost everyone, and that disappoints my post-modern heart. I can see that it's the best way for the franchise to close the Chell chapter and for everyone to feel closure, but the themes of the work completely change. In Portal, players come away feeling that physical rebellion might not be the best way to solve a conflict with a manipulative, powerful authority. Maybe if we could have negotiated with GLaDOS things wouldn't have ended the way they did. But Portal 2 keeps reinforcing the idea that since the player is the protagonist, the protagonist can "win."
I might be reading too much into it. What was your experience with the Portal games like? Did you feel like GLaDOS won in Portal, or was that just an excuse to have a sequel?