I guess the important at the will be the capacity of Jane to kill, or not, Red John. The show it's about Patrick Jane, the mentalist. They will make it about him.

Actually, Red John is like an octopus, when he needed something done he would ask one of his followers. If Red John isn't a concept, a doctrine or something like that I would say that he's someone who never appeared. Lorelei told Patrick that he shaked hands with him but she could bet wrong, she actually thought that she was dealing with Red John but the guy could just be one of the "3 dot tattoo". That way the surprise would be bigger.

My guess is that Red John is a title, like a rank. The person in charge is Red John. But the actual organization is Red John. When Patrick realizes that he will stop his desire for blood and will help Lisbon and his friends at CBI to take down the entire "tiger tiger" crap. But all I'm trying to say in my bad English is that I don't really care who Red John is (or what is). I'm more interested to stop figure this one out and enjoy...