I just received ICS on my moto xoom yesterday. I was excited because I kept hearing about how much faster and smoother it was. After installing it and playing around with it for a while, I was able to say that it was faster and smoother, but not as much as I was expecting. I did a little research and found this.
Under setting > developer options > force GPU rendering - I made sure this was checked
I set the Background process limit to 3 processes.
WOW! It made a difference with many things. I mostly use my xoom to view PDF files for work. Many of them have hundreds of bookmarks in the PDF's. Before I made these changes, my bookmarks were very slow to scroll, lots of hesitations when scrolling the bookmarks, and very slow to respond. Now they are smooth as I could ever want without hesitation.
You might want to uncheck gpu rendering. There are apps that don't support it. I know Instagram is one. When you open it it'll tell you to turn off gpu rendering. I'm guessing they build it in to most apps now so there's no need to force it. I'm no expert on the subject though.
WOW, I apologize. I made these changes and it absolutely makes a big difference in PDF documents with a huge amount of bookmarks using Quickoffice pro. All the rest of the improvements I now believe is a placebo effect. I changed it back and found the only difference was in Quickoffice pro.
My bad. I should have researched it a little more before posting this.