In particular, the circle jerk goes as follows.
Andrew Gilligan was "resigned" from the Beeb over the David Kelly affair, and rehabilitated by Johnson at the Spectator. He then moved to the Evening Standard, where he led an unapologetic campaign to "get Ken unelected". The Standard is part of the Daily Mail family, as is the dire London Lite. The decision on which free rag gets given to Londoners on the tube is coming up, and will be taken by.. Mayor Johnson.
So the whole thing is best understood as a battle by a propagandist and rabidly right-wing rag to protect its control over its audience. Boris may or may not be Cameron's loyal puppet, but he's definitely Associated's puppet. Think about it. "Dave" may or may not be Prime Minister when LOLBoz is up for re-election in 2012, but the Evening Standard will be there for sure, ready to re-elect him or destroy him as circulation demands.