This is a fascinating time for both clubs and their TV rights. What the Cubs do may open up opportunities for the Sox or crowd them out. My bet is that the Cubs may choose to try and buy their way out of he CSN ownership and remaining years of the contract. They will then attempt to form their own network with a partner, as was done with the Dodgers, and leave WGN after 2014. The busses from Iowa don't mean a thing compared to the money that the Cubchannel could drag in.
The Sox remaining with CSN is still strong with the Bulls and the Hawks filling programming and maintaining a strong package to sell to cable operators. The trouble for maximizing revenue is that the gorilla in the room is Comcast, which would mean trying to cut a deal with their corporate partner. Don't know if the Sox would want to increase their presence on WGN, but they may be able to squeeze more cash out of them to make WGN America viable.
Final 2014 Home Attendance Record 5-11.