What differentiates this from all the other social shopping sites out there?
Also, I'm not trying to build another social shopping network. I'm looking more towards Twitter+FriendFeed integration. Twitter may-not provide better shopping related feature-set. Similarly, FriendFeed may not add all social-shopping services like Kaboodle, ThisNext, Kirtsy, etc., which I'm planning to add soon.
These are primary reasons. Hope this answers your question.
The idea is compelling when you extend an API considering the giants of ecommerce tend to close off their reviews, recs or community posts on their sites.
We should talk more offline as I've been working on something that could mesh well with your app throughout the entire shopping experience (pre, during and post checkout).