A while back I asked for quotes about our development process to use in the presentation that Mark and I were doing for linux.conf.au, and we got one quote that pretty much summed up why our dev efforts have been so successful, IMO:

I recall one moment in IRC when someone submitted a patch to a much-wanted bug, there was massive cheering, and the dev said wistfully that this was why he was wanting to submit patches here and not at the day job, because while the day job paid, it did not provide a cheering squad, much less a genuinely enthusiastic one, and as much as he hated to depart, his dayjob beckoned. (And then I pointed at *that* and hailed non-dev channel denizens and reminded them that their contribution of hanging out and cheering was indeed a valuable contribution with real benefits.)

That's why it's been working! People love that moment of seeing someone jumping up and down and squeeing over something that they just did. (I know I do ...)