Reading the latest Economist on the plane back from Chicago, I noticed the following paragraph in a piece on Unix's Founding Fathers:
Linux is also the true heir of the Unix tradition in the sense that its development process is collaborative. Dr Pike says that the thing he misses most from the 1970s at Bell Labs was the terminal room. Because computers were rare at the time, people did not have them on their desks, but rather went to the room, one side of which was covered with whiteboards, and sat down at a random computer to work. The technical hub of the system became the social hub.
In my limited experience, having an informal hub like this is deeply important. Stewart Brand makes this point in How Buildings Learn -- one of his favorite examples is a building on the campus of Princeton University that contains unavoidable common spaces where scientists bump into each other, thus encouraging cross-pollination. I think it's possible to find similar hubs in the virtual world; for instance, the early Jabber developers never met IRL (that's "in real life" for you non-IMers) but spent countless hours in the #jabber IRC channel, which was eventually superseded by the jdev room on conference.jabber.org once we got groupchat to work and were able to eat our own dog food. The jdev room is still a place where smart people come together, share ideas, argue, and improve the underlying Jabber technology. Be there or be square. ;-)