Last night's presidential debate was the most-tweeted about political event in U.S. history, proving once again that Twitter has become the indispensable tool for following current events. There were over 10 million tweets during the 90-minute debate last night, dwarfing even the combined number of tweets of all the debates from 2008. Twitter posted a minute-by-minute chart of the flow of messages on its blog last night, showing how interest peaks and wanes at key moments. The most-talked about moments seemed to be any time one of the candidates argued with moderator Jim Lehrer.

There were also at least three, and probably more, fake Big Bird accounts created as an immediate response to a single throwaway line by Mitt Romney about PBS funding, showing how quickly a meme can be born and die.

Personally, we're not even sure how people followed the debate on Twitter, as the volume of comments had our Tweetdeck column moving so fast it was impossible to keep up. Even so, the idea of watching such a key national event without the instant reactions of your fellow tweeters has become almost unthinkable. If you're just watching on TV and not taking part in (or at least following) the simultaneous online conversation, then you might as well not even be paying attention at all.

Of course, participating in that conversation has its dangers too, as the humble appliance maker KitchenAid discovered after a rogue tweet last night, posted and quickly deleted after President Obama mentioned his late grandmother. It read:

"Obamas gma even knew it was going 2 b bad! ‘She died 3 days b4 he became president’. #nbcpolitics”

Yes, even damage control can be part of the national conversation.