Even if they DO announce (and that is still speculation at this point), there is no guarantee of government approvel.
Lots of folks in Congress would be concerned about the loss of jobs and the reduction in competition that would probably result from any merger(s). Unions representing airline employees, too, could fight any consolidation unless they get guarantees for better job security or better pay in some instances.
Just look at how many employees fared in the US - AWA merger. I'm guessing the unions and Congress will definitely wrap this up in debate and discussions for a LONG time...