feedback from other developers is mostly worthless
TJ had an interesting post yesterday on some new features he's added to iKollect and where they came from. The key observation he makes is that feedback from other developers and passers by is completely worthless for the most part. That's why I long ago stopped asking for feedback on forums and the ilk. Someone coming to your site and giving you ideas for your product based on a one minute assessment is just a waste of both people's time.
This is even more true for sites like TJ's that are not geared for developers. Getting feedback from programmers for a site designed for collectors is only going to pull you in the wrong direction. Your time is much better spent researching your market, listening to customer feedback, and following your gut instinct.