Larry Page confirms that Google Glass is running Android
The comment came in response to a question about what kind of engagement increase companies should expect with new products like Glass. Page responded, “Obviously, Glass runs on Android, so [Android] has been pretty transportable across devices, and I think that will continue.”
So, that answers that. It had been assumed that Glass ran Android, but there had also been some speculation that Glass was running a custom OS that was separate from Android. Maybe it didn't really need confirmation, but we're glad that's been laid to rest anyway.