Here's roughly the first third of an interview with Peter Moore conducted by mercurynews.com.
The interview took place Thursday, before his participation on a panel devoted to "Taming Gaming in Your Home."
Here is a brief highlight from the interview:
Q (Mike Antonucci): And people would jump in and say, fine, but, the biggest successes Microsoft has had in gaming is with M-rated titles. Be a better corporate citizen, find an (entertainment) platform that's successful that doesn't have an M on it.
A (Peter Moore) : ...If the reference is to Halo, I'll stand by Halo. Yes, it's a M-rated game because of the criteria, the quantitative criteria that the ESRB rightly puts in. But it is something that I felt comfortable (with) when my son was 16, maybe a year under the age. And I may be going out on a limb here: Yeah, I felt comfortable when he was 16. Did I feel comfortable with other games? No, and I wouldn't let him play them...