Weclock: so we're talking about game publishers and not developers eh?
so derek smart is a game publisher and not a developer?
The original point was that the best-selling games on Xbox 360 are Microsoft-games. And that's what they are. Some were developed by other companies, but funded, published, distributed and owned by Microsoft, and that makes them Microsoft-games.
As for Derek Smart, he is both a developer and some situations his own publisher. His latest game, Echo Squad, was published by his own company (and distributed by Gamersgate). I'm pretty sure he'll try to self-publish the MMO he's working on too.