I know this is an old thread but I thought I'd clear this issue up for anyone who comes across this thread in the future. The Rezound can take screen shots two ways. The first is the native screen shot feature which is power button and home button at the same time. The second is the ICS screen shot feature which is the power button and the volume down button at the same time. I hope this clears up any confusion.
Sent from my HTC Rezound using Droid Forums
Droid does...Apple bites