Yeah he did. In his interview on GT, he was very excited.
I didn't pull all his quotes (there's a great part of the interview where he's rubbing his hands together like a Mad Scientist that I HOPE we'll be seeing in .gif form soon) but here were two pull quotes that Sony will be ecstatic to hear:
Mark Rein on PS4 and Unreal Engine:
Mark Rein: "They stepped it up, there's no question. I mean when we made that demo we called it our 'Love Letter to Hardware Manufacturers'...and someone answered our letter."
...
Geoff Keighley: "Is it enough for five or six years? A lot of people were wondering about the leap was going to be. Pete Hines from Bethesda said here the leap between from ps3 to ps4 was not going as great as 2 to 3 given the move to HD and things like that…"
Mark Rein: [interrupting] "I disagree. NO, I think this a big leap.
The PS3 was decent…but this is spectacular."