edit: In summary, the more pairwise interactions between people your team has, the more likely they are to be a productive, successful team. Open office plans lend themselves to more serendipitous interactions between people.
My 2c, is that open office vs closed office is simply a matter of tradeoffs. It seems easier to 'opt-out' of distractions (by putting on headphones) than 'opt-in' to interaction (by say wandering the halls talking to random people in their cubes.) People who complain about open offices probably are complaining about a culture where an open office results in distraction, not the office itself. If you have a culture where people can be sitting next to you but can signal they shouldn't be interrupted, or there is ample quiet space for private work to be done, you can have the best of both worlds.