Tuesday's 'Piers Morgan Tonight' (Weeknights, 9PM ET on CNN) was a special edition about Twitter, in which 'New York Times' columnist and foreign correspondent Nicholas D. Kristof explained how the microblogging network has been keeping dictators in the Middle East in check during the anti-government protests that have been sweeping through the region.

Kristof explained how when he was covering the uprising in Egypt last month, and he saw pro-Mubarak "thugs" out among the protesters, he would immediately tweet "Mubaraks thugs out here holding clubs with nails, better look out."

"You can likewise take a picture of the person, and then Twit Pic it," he continued. "So then there's a photo of that person going out, and it enormously raises the cost of repression for regimes."

"It holds dictators accountable," Kristof added. "And one reason we're not seeing more atrocities in the Middle East, frankly, is that everybody knows there are people Tweeting, there are people taking photos, and the word is getting out."