I would say read the text he quoted
The best thing you can do to retain root is to decline the update when the prompt shows up. Wait a day or two for one of the devs to turn the 4.0.3 update into a flashable zip and you'll be good to go. The other thing you could do right now is flash a custom rom. This will give you 4.0.3 right now, plus you won't have to worry about losing root.
Damn, this thread has been quiet for a couple months now! I'm probably one of the very least who hasn't rooted yet :P
Going to try this method. Hope I don't run into any problems
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Haha, yeah never mind. I thought I had to actually use adb and stuff. It does it automatically. I skipped the system variables part since it was optional though. I got through the drivers part and just backup up my data. Ready to unlock and root