I think if the 7 suspect list is correct, then it can be narrowed down to 3 people.
Red John shouldn't be:
Sheriff McAllister because he saved Jane the last episode by climbing the ladder onto the roof (not acrophobic, maybe),
Reed Smith is too large according to the way Rosalind Harker describes RJ,
Bob Kirkland is seen in the preview of the next episode (Red Listed) as torturing Jane for the real list of RJ suspects. RJ already knows the list of Jane's suspects, and
Brett Partridge is dead.

Obviously all of my reasoning could be wrong and it is just RJ's way of throwing us off his trail...
for example Brett Partridge could be alive and be the one that tazered Lisbon, who knows.
Did anyone catch Sophie Miller's (Jane's psychologist) patient named something 'Washburn'. Remember Walter Mashburn? silly coincidences like that are made to confuse and annoy us, haha.

I strongly think it is Bret Stiles, but I definitely think that Red John is someone who has strong feelings for Lisbon (making his smiley on her face). Someone like Ray, who stopped by her hospital bed. I haven't watched the older seasons but I also think that Bertram and Stiles liked Lisbon, too. The other 4 suspects don't/didn't have any relationship with her...
So there you go. Bret Stiles, Ray Haffner, Gale Bertram