I am curious to learn about this. Would you care to provide a link ? Is it something available only to Google Partners or everyone in general. A lookout on web for this doesn't fetch me anything relevant.
Also, I believe (but am not 100% sure, and certainly don't want to be quoted on) that: 1 - AFS pays very competitive rates; 2 - in order to get an XML feed, you will probably have to agree to exclusivity. This isn't all bad though as you often get a better rev share if you go exclusive. Typical periods are two years.