Guy Kawasaki reports on a UCLA study he found, "The Availability Heuristic in the Classroom: How Soliciting More Criticism Can Boost Your Course Rating." According to the study, two groups of students were asked to evaluate a course. The first group was asked for 2 ways to improve the course and the second was asked for 10 ways to improve. Interestingly, the group that was asked for more criticism actually reported higher levels of satisfaction with the course. The study seems to indicate that the more you solicit feedback and even criticism, the greater the likelihood that your service will be rated positively.
Of course, the study may apply only to course evaluations. But it does seem to have some potentially interesting implications for nonprofits deciding about whether or not to solicit feedback through blogs and other social media.