The folks over at XDA-Developers have posted an unofficial Changelog for Android 4.0.4 along with the ROM. One update that stands out to me is the new radio update which handles the CDMA/LTE handshake better than the previous radio did. I am noticing the switching to 4g in place I don’t really get 4g and hold the signal for a short time til it goes back to 3g which to me tells me the handshake is working smoohtly. The good news is Rooting Android 4.0.4 isn’t really that hard and took about 2 minutes so head over to Droid-Life will explain the Rooting Android 4.0.4.
Don’t forget you will need the Android SDK(adb), flash-boot(Windows, Mac, or Linux) and ClockWork Recovery.