Being involved with plugins (not jQuery) I've struggled with working out the best way to curate quality. User ratings? Self-certification? iTunes-style pay +

Being involved with plugins (not jQuery) I've struggled with working out the best way to curate quality. User ratings? Self-certification? iTunes-style pay + review? Combination of all of the above? Certifying code quality (whether free or paid) is a tough thing to do, yet it's going to be massively important going forwards. I'm keen to here of how the new jQuery plugin site plans to tackle this.