StacyPete, have your sales been from your existing collection, or did you reply to any of their Picture Calls? Either way, have you done anything with their Picture Calls?
I went ahead and joined (the basic account, not a paid account yet) and am trying it out.
I find their Picture Calls especially interesting -- it's just like what Photoshelter Collection had (I still can't remember what their term was for it), but essentially a buyer can request a certain image type (essentially spec'ing a shoot) and you can reply to their requests (with existing images, or you go out and shoot it!).
I find that attractive myself, just because I like/prefer assignment-photography vs. coming-up-with-something-on-my-own. I'm sure that says something about my personality and/or creativeness, but whatever. ;) I just enjoy assignment work...
To me, it's like combining one of the best parts of DPC (the challenges) with one of the best parts of stock photography (i.e. getting PAID!). ;)
With the basic account, you have 12 photo slots -- which I'm going to use for Picture Call submissions. You could conceivably "rotate" your slots to respond to different Picture Calls, but I haven't figured out yet how to tell when it's safe to remove old submissions (I just joined, and am going to do my first submissions this week). Either way, I figure if I sell a couple of shots from that, that will easily pay for a full membership and I won't worry about rotating slots.
I'm sure some won't find it attractive, but for someone like me who doesn't have a large collection of existing stock-worthy shots, I like the "assignment" feel of the Picture Calls; if nothing else, it keeps me shooting and building more stock shots to add to my own collection.
If anyone else finds it interesting enough to try out (even just the basic, non-paid account), you're welcome to use my memberid as the "promotional code" on the sign-up form. I'm not sure it does anything special for you right away, but they are doing some promotion where if you refer some number of people, you (temporarily at least) get a higher percentage on sales (so it helps me by the referral). ;) Anyway, if you want to use mine, it's 21010.