Hey, I promised I'd get back to you guys when I got the phone:
I tapped on the glass, and it has a slightly lower pitched sound... possibly due to the fact that it is bigger in size. When I look at the reflection of the screen, the glass on the HTC Thunderbolt has a more accurate/optically perfect reflection (if that makes sense). Attempts to scratch the screen with my car keys resulted in the same results as Gorilla Glass. I'm not going to try any more strenuous tests than that, but, for what it's worth, I'm not going to use a screen protector.