In essence, the chairman of General Electric (which owns MSNBC), Jeffrey Immelt, and the chairman of News Corporation (which owns Fox News), Rupert Murdoch, were brought into a room at a "summit meeting" for CEOs in May, where Charlie Rose tried to engineer an end to the "feud" between MSNBC's Keith Olbermann and Fox's Bill O'Reilly. According to the NYT, both CEO's agreed that the dispute was bad for the interests of the corporate parents, and thus agreed to order their news employees to cease attacking each other's news organizations and employees.
There are a number of implications of this story. Among other things pointed out by Greenwald, the GE/Fox deal is strong evidence of corporate control by companies like GE over their news divisions. I would also think that the deal also demonstrates the limitations of any effort to bring progressive ideas and personalities into the mainstream media. If corporate headquarters at GE, Disney, or TimeWarner can decide that a huge right-wing target like Fox is off limits, then it's pretty evident that progressives won't be able to get very far with the corporate-owned media.
The GE/Fox deal also looks like an obvious violation of anti-trust laws that discourage this kind of collusion.