When a book is the chosen top read in Factbook, it's cover is more prominent than when it is the actual pane and it gets a tiny thumbnail.
If the style matched that of the factbook, I think it would help me better remember which resource I found a particular point in while digging through my library each week. Those visual book covers can act as "mnemonic buckets" for users if it's more than a tiny cover in the panel toolbar.
