So I am looking into how the developers of Super Meat Boy and Fez published their XBLA games through Microsoft and I was wondering about the XNA exporter being used with this. I'm aware that there is a Steam extension which is granted to anybody who gets accepted into Steam (which is now a little more likely thanks to the greenlight system), what are the chances of something like this for XBox Live Arcade, i.e. interacting with achievements, leaderboards and the like, for any user who might manage to get in with a publisher or MS themselves? It'd be great to think that truly serious developers could use MMF as their SDK. What's the likelihood of this being possible?