Before the season started I thought RJ was Partridge.  First episode when Partridge was killed I just thought he faked it and it was still him.  Now that we've allegedly seen his body I'm probably wrong? But who knows. Who ever it is I think its one of the "dead" suspects, not Bertram or Smith.

In any event whats more unbelievable is how Red John holds down a full time job, is a serial killer, has followers, founded the Blake Association (and make sure it runs the way he wants), and was or is involved with Visualize.  

How does he find the time in the day to do all this and make very few mistakes that would lead to his capture.  That's the real mystery to me :)