For several weeks Iran has been closed to the media. All foreign correspondents have been ordered out and Iranian authorities are doing all they can to dampen any hint of protest.But it is not really working. Word is still getting out; citizen journalism has taken hold.It is not unusual that foreign journalists are expelled from a country when there is a big story because visas are still the most powerful tool that authoritarian regimes have to block out communication to the outside world.They just keep journalists out. They block the phone lines. They can block SMS messages easily and that is what happened in Iran.Normally that would pretty much be the end of the story. We would hear a little bit about it for a few weeks but then it would dip out of the headlines. But what is unique and historic about what has happened in Iran, is while there may not be a revolution on the streets, there has definitely been a revolution in media.For the first time we are seeing a situation where foreign journalists cannot report what is happening.