We were waiting on Hany Farid to give answer to the question: planes or no planes? but it seems "achimspok" has answered already. Simon Shack's best argument for coordinated video feeds into the networks was the 17 second glitch (prior to the second impact... the live money shot) which was alleged to be common to several of the broadcasts. But it is shown to be not so. The viewer can check for oneself: Fox5, ABC & CNN.
Other points are covered in the series Comm' On 9/11 TV Fakery & No Plane Theory