Not that Bush should have made those faces but watching the video, one could also make the case it was done by the RNC to show the ludicrous statements made by Kerry. The added music made it even more humorous.
People know Bush and this is how he is. We have experienced 4 yrs of Bush and know how he handles himself.
That's why I think Bush won the debate. Maybe he wasn't as polished, maybe he looked tired or whatever, but people know this President, and that's who showed up and told the truth last night. Funny faces and all. :-)