Including the Customer
This is about the gajillionth article I've read that says that Open Source software squishes bugs faster. You know what? I don't care.
What I do care about is the fact that Open Source software includes me in the bug squishing process.
In September 2004, I filed bug #477 on the MediaWiki bugzilla. There was an initial flurry of activity about my bug, which tapered off as the weeks went on. But my bug was never abandoned; and each time someone weighed in with an opinion on my bug, I received an email about it. Even now, over a year later, I still get emails when someone adds something new. Twice I've received emails from the bug tracker alerting me that other bugs have been marked duplicates of mine, which further validates the fact that my bug report is legitimate.
As a user of the MediaWiki software, I am extremely pleased that I've been kept in the loop. I've learned a fair bit from the discussion on my bug. Even though my bug isn't officially fixed yet, I'm still more inclined to use MediaWiki than a competing package because I value the inclusion that I've received.
And the thing is, the people commenting on that bug aren't even trying to include me. They've never addressed me personally; they haven't sent me private email. But the bug tracker in use -- Bugzilla -- includes me by default, encouraging my continued participation in the bug squashing process, and encouraging me to remain involved with the larger MediaWiki community.
Compare that with most any closed source software application, where your bug reports disappear into the ether. Granted, some closed source applications do provide some follow-up to their bugs, but even these don't let the original reporter see so much of the developer conversation as what you'll find in Open Source projects.
Open Source is a great model for developers, but it's also a great model for customers.