A bit of biz feedback, as e-readers with locked-in formats become the norm (ebooks are now outselling physical books I believe), where do you see the opportunity for growth in your site?
Though I agree with nagarch about design, I don't think the design is THAT horrible. You've done a fine copy of pintrest. As a UX is just might not fit this use-case very well.
But if you're looking to build a business of this, make sure you've got a big enough opportunity.
Also, the price on books seems to only be a dollar here and a dollar there. Is this a big enough difference for people to leave their regular bookstore?
