Twelve hours ago CNET News’ Daniel Terdiman reported that ‘as the Iranian election aftermath unfolded in Tehran — thousands of demonstrators took to the streets to express their anger at perceived electoral irregularities — an unexpected hashtag began to explode through the Twitterverse: ‘CNNFail.’

“Even as Twitter became the best source for rapid-fire news developments from the front lines of the riots in Tehran, a growing number of users of the microblogging service were incredulous at the near total lack of coverage of the story on CNN, a network that cut its teeth with on-the-spot reporting from the Middle East.

“For most of Saturday, CNN.com had no stories about the massive protests on behalf of Mir Hossein Mousavi, who was reported by the Iranian government to have lost to the sitting president, Mahmoud Ahmadinejad. The widespread street clashes — nearly unheard of in the tightly controlled Iran — reflected popular belief that the election had been rigged, a sentiment that was even echoed, to some extent, by the U.S. government Saturday.

“‘The Obama administration is determined to press on with efforts to engage the Iranian government,’ the New York Times cited senior officials as having said Saturday, ‘despite misgivings about irregularities in the re-election of President Mahmoud Ahmadinejad.’

“Yet even as word of the urban strife, seemingly led by those posting to Twitter, spread next around the world on news networks like the BBC, NPR, and the Times, CNN remained mostly mute. Even when the network’s Internet site finally posted a story late Saturday, the network’s first ‘story highlight’ was, ‘Ahmadinejad plans rally after winning second presidential term.'”