Earlier quoted context omitted.
Free membership which accumulates points. These can be spent on books. Books are priced in points according to a metric (TBD). Bad books are 0 points. You can also get points by bringing in good books. (It's like uh some kind of currency based barter dude ;) )
It sounds like physical bittorrent
With the difference that with time you get free credit automatically. Perhaps somewhat comparable to optimistic unchoking in BitTorrent :)