If so what are the titles? Does any of them relate to the RPGMs at all? I thought there was one person here using XP or something to make these games. Do all XBOX Live games require XNA software, certification, etc.?

Don't have a clue, but I'm sure there would have been a lot more fanfare if someone did.

I think there was that guy promoting XP-only, and even then it was limited.

From my not-so-often visits to the official PCRPGM site, they HAVE been taking polls, and gauging interest for people who want the tools in order to make their games available on smart phones, and XBL. Though, knowing them- it probably won't end up as an option til the next RPGM after VX Ace comes out... and that's still a major if.