I saw the exact same thing happen to Steve Jobs during an Apple key note address a couple of years ago. Turns out the batteries in Job's remote were dead. Pretty embarrassing for him, though.
Big difference in dead batteries causing a remote to fail and software that is so buggy one considers it a good day when something doesn't go wrong. However, we all love to see CEO's go down at a marketing event (unless of course it happens to be you or your boss using your gear!!)