Thanks Atomizer for the feedback - always welcome.
1. That should be possible and it is added to our development to-do list.
2. Nice idea, but I don't think that would be feasible. We are limited on the number of calls we can make to the Amazon API and if someone with thousands of books wanted to know the value of their collection, that would probably tip us over the limit. All our other API requests are low level such as importing data for new books.
3. We have been asked before about getting involved in cookbook swaps or cookbook sales. We are definitely avoiding that area. No matter how many qualifiers we put in our terms & conditions (which most people never read anyway) members will still ask us to intervene in disputes - I paid for the book and it never arrived, the book was damaged and the seller won't refund me, the quality is not as it was described, etc.
4. That's a good idea and has been added to our list. Ranked top 10 or equally best top 10?