Twitter cofounder Biz Stone posted a chart showing the frequency of political keywords during Friday night's McCain/Obama debate. "Iraq" hit the highest rate of tweeting at a given moment during the event, followed by "tax" and then "Korean" after John McCain deemed North Korea "a huge gulag" that stunts its citizens' growth by three inches. But the trick to reading a chart like this is to look not at the height of the lines, but the surface area under them — that's how you measure the total number of tweets for that keyword. Iraq and taxes look to be the biggest. But Stone's chart shows Iran and Russia, not Koreans, are what everyone's tweeting about.