First of all, I don't think Red John is on the list, for several reasons:
- the Mentalist isn't built as a common police movie with cases being solved by grueling grunt police work; the cases are solved by Jane's analytical brain and by his tricks, so the villain being caught by a dull process of elimination from a list given in the previous season would be against the spirit of the series
- if Jane really thought that RJ is on the list, he would have taped the 7 suspects talking and bring the tape to Rosalind Harker. He would have studied her reactions to hearing their voices and at the end asked if she recognizes anyone. The only reason PJ didn't do this is because he knows RJ is someone else.
- the list is fake as was the one left for Kirkland and is probably composed of tiger tiger members; Jane deceived his team before, he wouldn't trust them to keep the secret of the real suspects
- Heller only said that we can trust the list; that seems to me rather ambiguous, and precisely this lack of directness leads me to think that RJ is not there. He could have said : "Yes, sure, Red John is among those 7", and it would have been clear. Probably, the list contains the other bad guys, the corrupt cops.

None of his teammates could be RJ, beacause otherwise Lorelei would slip an information more relevant than  the simple: you shook hands with him.


My money is on Ellis Mars:

- he appeared before season 4; Heller said at the beginning of season 4 that RJ had already appeared
- he was a more of a background character in the Red Moon episode; Heller said that finding RJ is like finding Waldo
- he was in Jane's extended list of suspects
- he played the part of a bumbling fool who claimed he had psyhic powers, knowing that PJ wouldn't take him seriously; in an episode there was a criminal that pretended to be a half-wit but eventually got caught. Moreove, some serial killers like to stay close to the police and pretend to help them, as did Ellis in Red Moon
- he pretty much fits Rosalind Harker's description
- besides the fool act, he seemed well spoken and partial to wearing suits, just like RJ
- the most important clue: the message left by the hooker in Mexico: He is Mar. As others pointed out, "he" in spanish is el, so: EL is Mar, or Ellis Mars
- Mars, his name, is also the name of the RED planet

Just my two cents. :)