Requiring a user to type in a zip code for the registration is awkward when all that is required is a country (and zip codes only apply to the united states).
I like how it find matches for products that have already been entered when you submit a new one, but it seems that only the first submission will set the product's URL and description, which is what most people will see when they view an item.
Also, it's not obvious at first what URL should be submitted for a product. I wanted to add 'Blast Corps.', but still am not sure what should be done for a product no longer in retail.