I've also worked in both, and have been far (far) happier in an open office layout, to the point where I'll never work in a closed-door office layout again. It's so isolating and depressing to me. Sure, I could get into a flow -- that's all I could do. I'd go to work and work for 8 hours a day, not talking to anyone. A pretty miserable existence.

Also why I could never work remotely/from home, I guess.