I see Penguin merging with Random House as hiding behind their skirts; in other words, if Random House decides to continue with the agency model, Penguin will be able to do so, too.
If they all go back to the agency model in 2015 we will be right back in it, and nothing will have changed. Also, they went into knowing they were losing money per book (being paid less by the retailers). I don't see how they could have made more money with it, although Random House claims this was its motive for changing to the agency model after watching how things were going for the others for a year.