This is a previous theory:

For those of you who think Red John is one of the remaining 5:
Rigsby says "Red John brought in the bomb to kill Jane and the other suspects"
If any of those 5 were Red John, why would he plant a bomb in a room that he was going to be in, just to kill himself, Jane, and the other suspects?
Answer: they wouldn't. There would be no point for Red John, this extremely prideful, narcissistic, showman of a serial killer, to plant a bomb to kill himself and his nemesis, along with a few others. Really, if you were Red John, would you waste 20 years of killing people just to die in an explosion with no one knowing that you were actually Red John? No, you wouldn't. You would make sure that, if you were going to die, everybody would know who you were so you would leave a lasting effect on them.
And if it is true that Red John is on the list of 7, then we can eliminate the 5 ones that are definitively alive because of the explosion. That leaves Bob Kirkland and Brett Partridge. Bob Kirkland is definitely dead, we saw him get shot in the back 7 times. That just leaves partridge.

Ok this got me thinking we know partridge is dead SO the only possible explanation IS Bob Kirkland IS ALIVE (or is it his twin!)

When he asks "do you know who I am" to people he is seeing to try to find his brother who was apparenty taken under Red John's wing a long time ago. But what if the old red john stopped killing because he died (which is why red john was said to stop killing for a few years) then Kirkland's twin brother took over as "red john" ? It makes perfect sense! We were told by the producer of the Mentalist that the list is 100% legit meaning red john IS 100% someone on the list! Kirkland's twin brother is Red John! Please comment to share you're thoughts!

I don't have a theory, I have some questions that I'd love to see you commenting and trying to answer.Please read my questions because I'm STUCK.
1)S01EP11: What's written on the wall, by who and why???
http://images2.wikia.nocookie.net/__cb20131029111127/thementalist/images/4/44/Mentalist-heisman.png
2)S01EP23: How is it physically possible that Rosalind Harker (the blind woman) found a card of Red John under her sofa, read it, wrote and sent a letter to him??? (note that she stated clearly that she lives alone with lack of any kind of connections with the out-of-her-house world)
3)S02EP08: Who killed Rebecca, and why did she smiled at him when she was about to die???
4)S03EP03: How comes Bret Stiles knows about the place that Red John kept Kristina Frye captured?Is that suggesting that Bret Stiles knows Red John's identity?
5)S03EP23: Why LaRoche kills the black guy while there are cops everywhere?(He justifies "because he tried to escape" - Looks similar to the Bob Kirkland case)
6.S05EP16: Lorelei' s being shot by a cop at the arm while she tries to escape.
S05EP18: Two weeks after(!) she's found dead with no signs of arm wound.(I think it's quite impossible that a wound from a bullet is healed after only 14 days.)
S05EP22: Lorelei appears again, (at the video made by Red John) and this time the wound from the bullet reappears(...)How is that possible?
7)S05EP22: How comes Red John knows the 7 names on the list Jane made, BEFORE him?
8)By the 7 men on the Jane's list, only Robert Kirland , Brett Partridge, Bret Stiles and Ray Haffner respond to the description of Rosalind Harker's about Red John.Gale Bertram: Taller, and bald. Reede Smith: Fatter, taller. Sheriff Thomas McAlister: Semi-bald with a mustache (that later shaved).This phenomenon concludes that Jane has no trust on Rosalind Harker.Why is that happening?
9)S06EP01: Why Red John doesn't kill Lisbon?It makes no sense since Red John tends to kill every possible person that Jane likes/loves.Examples:
His wife, his daughter, Eileen Turner (Jane's happy memory from the past) , Kristina Frye (not exactly killed but left in a very strange state-she believes she's dead), even Sam Bosco (when he started to have a more healthy relationship with Jane), Lorelei Martins, Sophie Miller (Jane's psychiatrist-He seemed to like her a lot)
10)S06EP01: Assuming Brett Partridge is dead, what's the reason for Red John to kill him?And why his last words were "Tyger, Tyger"?
11)Why Robert Kirkland kills Jason Lennon?It makes no sense because Kirkland admitted he was chasing Red John(same as Jane).So what's the point killing him?Why not interrogating him carefully like he did with the people from the fake list Jane made?Why the only thing he asks is "Do you recognise me?Did you see me before?It's important."???

*Sorry for my bad english.Please comment with your thoughts.

i'm pretty shure it's him !

Fully agree with the peoples who think Red John already dead. In the following episodes the Tiger-tiger clan will be unveild and with this  Red John will be named.
My guess is Bob Kirkland 
Red John and the Tiger-tiger clan are enemies for each other and both wants to kill other they but don't know the  others and don't know the persons
The only two person who had known the names are Patrick and Lorelai.
Since Lorelai knew she's sister was killed by Red John she also wants RJ death and getting contacts with the Tiger-tiger clan. But before she died left the message to Patrick with the 7 names.

In the episodes when Patrick was tortured by Kirkland wants to know the other names because RJ want to unveil the Tiger-tiger clan and murder all persons in the group.
Maybe  RJ  not as bad as we think he just killing the guilty person and the member of Tiger-tiger clan are the real criminalists.

Until the end of the season Patrick position will be changed from chaser to pursued.
The tiger-tiger clan want's Patrick death to avoid the unveil of the officers in high position.

And one other reason why Kirkland is RJ. Just have a look on the symbol and the face of Kirkland
FULLY MATCH.

If Red John would be the twin brother of bob kirkland i would be dissapointed!! It's like saying patrick jane has a twin brother and lisbon a twin sister.
That's bullshit, red john has to be someone of the mentalist show who is still alive not a twin actor thats plane stupid

Reasons for "Michael" Kirkland, Bob's twin brother.

1.) Loreli said, "I wonder why the two of you didn't become lifelong friends the moment you shook hands."  To me this implies they shook hands a long time ago, i.e. probably while Patrick was still at the carnival.

2.)  Bob/Michael Kirkland told Lisbon while drinking coffee, "We moved around a lot, for my dad's work and then mom's.  I like to say we grew up in America."  What profession makes you move around a lot?  Working at the carnival!!!  I think "Michael" Kirkland shook Patrick's hand way back when they were kids at the carnival together.

3.)  While drinking coffee with Lisbon, Kirkland calls Lisbon "Teresa" just as Red John says to Jane, "Sorry Patrick.  Teresa can't come to the phone right now."

4.)  In episode 5-18, Kirkland asks Lennon "Do you recognize me?  This is very important."  Why would this be Bob's only question to Lennon if he were searching for his brother?  All that torturing and interrogating of the fake suspects on Jane's list, he was tenacious and thorough.  If Bob Kirkland was interrogating Lennon, this would NOT be his only question.  "Michael" on the other hand would only ask this one question if he were Red John and wanted to be sure Lennon did not recognize him.

5.)  Just after killing Lennon, "Michael" Kirkland refers to Jane as Patrick.  "Patrick. It's terrible.  His heart just gave out..."  Red John ALWAYS calls Jane by his first name, Patrick.

6.)  None of the other suspects refer to both Lisbon AND Jane by their first names.  "Michael" Kirkland is the only one who does.

7.)  When Loreli is reading off Jane's suspects in Red John's video, the ONLY person she refers to by an informal nickname is "Bob" Kirkland.  Everyone else is referred to by their full, formal names.  Who would call Robert Kirkland, Bob?  His brother, Michael! :)
 

Twin brother. 

There was a scene showing them shaking hands and was kind of out of place. When red john is revealed as Bob Kirkland or Michael Kirkland (the twin) this scene will be played as a flashback where Kirkland said "but I know a lot about you" or some weird shit like that.

100% positive case closed

ggwp