The real killer feature is this: "Share favorite eBooks with your friends, family, or book club. Most eBooks can be lent for up to 14 days at a time. Just choose the book you want to share, then send it to your friend's reader, cell phone, or computer."
Oof. I haven't seen any definitive confirmation on one-lend-ever-per-title (they seem cagey about it), but looking at this purely economically:
This is by some measure a winning strategy, since if I only have one "lend", I will very likely want to share it to the person most likely to buy it and create an additional "lend" to propagate the book.
It does seem like they are missing out on the power of inter-consumer advocacy, i.e. "Everybody read this now!" They should at least re-credit you (if not several times over) if you share with someone who later buys the book.
It may give the illusion of a good strategy, but limitless invites will spread the book faster leading to more buys overall (in my opinion). Since many people like to own books they've enjoyed and the freedom this model gives also pleases consumers I'd prefer it.
Agreed, this is an aspect that would have always prevented me from ever paying for an ebook. As an avid reader I frequently give books to someone else to read, and handing over a $100+ eBook reader is an absurd prospect for loaning a book to someone.