Mine just finished updating... Not sure yet on what it was for.
I got it about a half an hour ago and so far I feel like the only thing they changed was the menu button icon in a bunch of Google apps. Now it is 3 vertical dots. I could be wrong but I feel like it was different before.
Besides that I don't notice any difference.
Updated just fine for me on a rooted device. Restored root with root keeper. Did not unroot before running the update.
You guys who have done stuff with root are brave. I'm waiting for the updates to slow down before I attempt any custom stuff. No need to confuse myself as to the cause of issues should they occur. I'm staying vanilla for awhile!!
Yes, I did delete some /system files, like email and calculator, that I would never use (since I use K-9 and Real Calc instead). I always have deleted those on custom ROMs on my OG Droid, so it's probably a bad habit I should have broken for my Prime.
Is there a system dump for the ICS update? I saw a couple that were posted before the ICS update and one deodexed version of ICS, but I'm not sure deodexed would work.