I'm actually in favor of developers getting a cut of used game sales, but this is the wrong way to go about it, and Microsoft itself has no right to any of that money whatsoever. It's their platform, awesome, but I don't see ASUS taking a cut of every game I buy on Steam just because I use a laptop they built. Not to mention the way this will distort prices. Just reading a recent Escapist article on the same, apparently retailers will be required to sell at 10% under the original RRP, rather than the up to 50% people are used to.
Unrelated: Because of the requirement for using Azure, if I want to give a game I own to a friend (Not common, but I've been known to do it when they like it much more than I do.) will I have to go to an Azure authorized retailer, sell them the game and then have them resell it to my friend, just so they can use it without my account?
Unrelated: Because of the requirement for using Azure, if I want to give a game I own to a friend (Not common, but I've been known to do it when they like it much more than I do.) will I have to go to an Azure authorized retailer, sell them the game and then have them resell it to my friend, just so they can use it without my account?