Here is the video:
At around 9 minutes and 50 seconds into the video, they ask him... If he goes back to Google, would he go back into the same role, in search? Watch how Matt Cutts answers the question.
He first praises the team there, explains he is not needed in that role because they do an awesome job. He says, "well, we will have to see how it goes." He did say he loved the part of the job keeping tracking of the news around search but he wasn’t sure being lightning rod for unhappy black hat SEOs is a good use of anyone's time. Like I said originally, it takes a toll on even people like Cutts.
It seems to me that if Matt returns, he would not return to the same role.
Now, will he return? Skip to 13 minutes and 44 seconds in, where Leo asks, "You won’t leave Google, Matt?" He immediately answers, "Well, I'll always have a connection and soft spot for Google."