It seems no matter if you're in a huge corporate project or a smaller cadre of independent developers, the rules of managing people and code remain the same. And open-source projects tend to manage people much better than their corporate brethren.
In projects with multiple people involved you have to continually worry about people leaving, contributing crappy code or going on a complete tangent. Usually in corporate life people just want the thing to work, and if it randomly happens to hit production and not have complete show-stopping errors, great. But the code could be complete cruft and no one would care.
With an open-source project, however, you must have complete transparency. Brian Fitzpatrick and Ben Collins-Sussman recently gave a presentation on managing people in OSS projects effectively. Code reviews, definite goals and communicating "just enough" were all key. Hrm... how many commercial software developers do the same thing?
It's not without its difficulties, however. Especially with the kernel, contributions can be a big mixed bag. Sifting the good contributions from the pointless ones can be time-consuming and tedious. So projects are split into more minute portions, and newbies are either mentored or given a sandbox to play in.
It seems like there is a role model out there for taking a wide variety of people with an even wider variety of backgrounds and time commitments and having them all contribute to a well-developed end product. It's a shame it isn't emulated more often.