lol. That'd be funny "Microsoft to buy GTAIV Exclusive content for 40 million MS points. Rockstar to download all content onto 3 Elite hard drives".
Just remember, you don't need to pay the "$50" (its more like $39) fee to get the content on XBLA. Heck, I haven't had a gold account ever, and I've downloaded tons of free and pay-for content.
Back from the dead, I'm afraid.