well, it depends. I have all my images set only at their FT license (like micro EL) and my last sale was in February. People who allow standard licenses report some sales. But very few people report sales - the forum however isn't a good thermometer for that. A few members appear frequently in the "what's selling" section.
I believe it may not be a good choice if you expect it to provide sales by itself. But I like their HTML tools to embed in my website, which I actually don't exploit much because most of my new stuff is uploaded as RM elsewhere.
edit: In any case, here is my referral.
http://www.shutterpoint.com?ai=MXHW75