The back story is an interesting one. Soon after I wrote and spoke about the covers opportunity, a major cover supplier contacted me. They were miffed at me, and at Google. Apparently a large percentage of the Google covers were, in fact, licensed to Google by them. They never intended this to be a “back door” to their covers, undermining their core business. It was up to Google to protect their content appropriately, something they did not do. For starters, the GBS API appears to have gone live without any Terms of Service beyond the site-wide ones. The new Terms of Service is, I gather, the fruit of this situation.
It’s always too good to be true! I guess I should read the terms through.