Mikey will put someone in that 55 car next year if the right opportunity presents itself. Honestly I could see any of the following 3 drivers at MWR next year in the 55...
Truex Jr - he's still not doing much at EGR. His contract is up - he will be making a move somewhere IMO. The only sticking point I see with him is the fact that I think he could easily move to become a 3rd car at Stewart-Haas or even replace Mears at RCR.
Danica Patrick - this is the type of signing that could get MWR all the attention in the world. I'm not saying that DanicaMania wouldn't become sickening like it is now in the IRL but it would be a good business move on the part of MWR. If he had her with Napa staying on board he'd have a big time sponsor for a huge superstar of a driver. I can see the new Napa commercials already with Mikey, her, Macy, Capps, Reuti, etc.
Kasey Kahne - this would be the one that would make the most sense for performance IMO. I do know that DW and Kahne have become pretty tight over the past couple of years. Kasey could be a good fit for a big sponsor as well.
Those are the 3 drivers I could see Mikey stepping aside from his ride for next year.