User blog comment:Rappy 4187/Technical Update: March 10, 2015/@comment-1251315-20150312231408/@comment-126761-20150313000201

Well, not just surveys - but it's intended a way for us to learn more about how more active users interact with the site.

It's rather experimental (hence no special announcement), subject to change, and confers no special benefits. We might have more to say on this in the coming weeks, but it's really dependent on how well it works. I wouldn't put much stock in who is or isn't tagged right now.