'Joe Wilson' top trending topic on Twitter

It looks like a Republican congressman's outburst on the House floor during President Barack Obama's address to Congress has momentarily eclipsed the speech itself, at least on Twitter.

"Joe Wilson," the South Carolina Republican congressman who shouted "you lie" at the president, is the top trending topic on Twitter right now. Trending topics track the most popular conversation subjects on the microblogging site.

"LIAR" and "R-SC" are also trending topics right now, meaning that three out of the ten topics are related to Wilson. "Obama" is the only non-Wilson topic trending about the speech right now.

Wilson made his comment after President Obama said that his health reform plan will not insure illegal immigrants. Wilson's retort caused the president to pause momentarily during his speech.