I find it interesting that in all these articles and studies about open plan offices, the distraction from noise levels is always so prominent, but the other side of that issue rarely gets mentioned. In my experience of open offices, everyone is so aware of potentially disrupting their colleagues by striking up a conversation that nobody does it. So instead of fostering an atmosphere of collaboration, the open office can actually actively prevent it. Is that as common as I think it is?
Depends on who gets crammed together. A bunch of developers in a room are possibly going to be pretty considerate about noise.
I was in an 'open plan' office where there were four of us developers at a large desk with a sales guy at one end, a sales guy sitting at the other end of our desk, and another sales guy ten feet behind him at a desk.
We were generally pretty quiet, but the sales guys liked to shout across us all day. That is, when they weren't on loud phone calls.