The concept of sharing your library over the Cloud is intriguing. The thing is, the way it works is extremely nebulous, because Microsoft has done such an extremely bad job of explaining it, perhaps because even they haven't finalized how it's going to work. It doesn't seem like they have, or if the developers get a say or can opt out of the system too.
The way I -think- it works from subsequent interviews to E3 (and the way I think it makes the most sense for it to work) is if it's basically like giving your disc to someone, it's just done digitally across the Cloud. So if your brother lives in San Francisco and you live in NewYork, you can buy a game and when you're done with and he wants to try it, you can "lend" it to him over the Cloud without physically having to give him the disc. Then he can play it, but you can't, until he "gives it back to you" digitally.
If you could lend games digitally like that, and still play them simultaneously yourself at the same time as whoever you lend it to, that seems open to abuse and not something developers would go for at all. It would basically be the death of single-player games. I also wouldn't want it to work that way - if a game is great (I'm looking at you, Thief) I want lots of people to buy it so the developers will make more of it, not for people to limit the sales by abusing the sharing system. But I have some close friends and family members who live far away from me and since I can't physically share my games to let them try them out, it would be great if I could lend across the Cloud. It would also just be a more convenient way of sharing even if people aren't that far away, rather than have to give and retrieve discs back and forth.
