I just think Steve has given John the benefit of the doubt and that's over. He basically came out and said he considered letting him go this past offseason and while he also said there was no "playoff or bust" ultimatum (he didn't want to put himself in a box) I think in the end it is absolutely make or break for John this year.
In the end it will come down to whether or not Steve feels we need a change to shake things up. I think he'll assess his view of team talent vs. team performance and make the call. If the season ended today, Harbaugh would be gone. Lucky for him, it doesn't end today. But to achieve what I believe needs to be achieved to avoid the ax - if not a long shot, is definitely below the 50-50.
Honestly - I am not hoping he gets fired - because he won't if we make the playoffs and make a nice run. That's still what I want.