Paul Ramsey swings his clue-by-four:
Open source is not about users, it is about developers. It is only about users in so far as users become sufficiently engaged in the project that they either become developers themselves, or support developers through careful bug finding or documentation.
I'd add that Open Source is for integrators too. End users not so much.
Update: Those of you who aren't persuaded by Paul Ramsey -- have a listen to Steve Ballmer.