While I've found all the myths chromatic listed during my time, only "Publishing your Code Will Attract Many Skilled and Frequent Contributors" and "End Users Love Tracking CVS" seem to be mainly open source myths. All the others seem to be general software development myths - many of which I have grown to love over the years :-)
Indeed "Programs Suck; Frameworks Rule!" seems to be more of a problem in the closed source world in my experience.
Actually, I have come across "End Users Love Tracking CVS" in the closed source sector too. Although in that case it was "End Users Love Tracking A Closed Source Control System That They Have To Pay For And Doesn't Run On Their Main Platform" :-/
I suppose there is a variation on the "It's Better to Start from Scratch" myth that applies more to open source projects - which is why we have *so* many templating systems, text editors, etc. All of which sit there at version 0.01 doing roughly the same sort of thing. The problem with scratching itches is that so many people itch in the same place, and nobody wants to scratch somebody else's itches (eww!)