News of the killing of al-Qaeda leader and terrorist Osama bin Laden broke first on Twitter, and has taken over trending topics across the Web.

Keith Urbahn, who worked as an aide to former defense secretary Donald Rumsfeld, was the first to announce bin Laden’s death in a tweet that preceded reports on major news outlets.

So I’m told by a reputable person they have killed Osama Bin Laden. Hot damn.Mon May 02 02:24:05 via Twitter for BlackBerry®Keith Urbahn

Urbahn later said that he received his information from a TV news producer, adding that one shouldn’t look to his tweet as evidence of the death of mainstream media.

While Urbhan may not think of his tweet as anything special, Twitter clearly emerged as a valuable news-gathering and sharing site as news of the death traveled.

Sohaib Athar, a software professional in Pakistan, unwittingly live-tweeted the raid on bin Laden’s compound in Abbottabad, Pakistan.

Search topics related to bin Laden-related trends shot to the top of lists on Google, which launched its news search engine after the Sept. 11, 2001, attacks, Search Engine Land’s Danny Sullivan pointed out.

CNET reported that while bin Laden’s death was a huge event on Twitter, it wasn’t the largest event in terms of tweets per second, a record held by tweets celebrating the Japanese New Year. Monday’s news hit about 4,000 tweets per second at the beginning and end of President Obama’s speech, about the same rate as the 2011 Super Bowl.

How did you find about bin Laden’s death?

Related stories:

Osama bin Laden buried at sea after being killed by U.S. forces in Pakistan

Sohaib Athar’s Tweets from the attack on Osama bin Laden - read them all below

Stocks Gain After U.S. Kills Bin Laden; Silver Futures Sink