I wasn't crazy about it, thought it was a little obnoxious personally, but have no problem with it. That's how sports stars are, it makes them who they are, and similar to what another poster mentioned, I get obnoxious when I beat a friend in a video game sometimes.
My issue was that the game wasn't over yet, there were still .4 seconds left. Derek Fisher anybody? Andrew Bogut? Not that I thought there was a realistic chance that we'd lose, but it was still possible and if we miraculously did... PP would have looked like the ultimate fool and I really mean ultimate.