I'm pretty sure that in the Gold seats it has to be raining money (paper, not coin) for them to stand up.
In general, the crowd was pretty into it all the way around. We were down near the endzone on the home sideline, and we only heard 1 "sit down," and it was early. I think it bodes well for the atmosphere you will see/hear on Saturday. Michigan fans won't keep quiet like Purdue fans did. Should be electric.