A few things to point out, 

First of all, that twin brother of Bob Kirkland is not RJ, we have never seen him, we haven't received any clues that point in his direction. It would be completely lame if he is RJ, which of course he isn't. 

Second, also stop thinking about Rigsby, Cho, Van Pelt and Teresa. This would also be completely lame, there are no clues leading in their direction and Patrick would have figured it out years ago. 

Thirdly, please read the theory below. I have read quit a few theories, but this is most definitely one of the best. It explains why Brett Patridge is RJ, and I agree completely. 

Certainly worth reading! 
http://www.whoisredjohn.com/See-a-theory-Red-John/8587

Finally, 
I just wanna say that it would be wonderful if RJ is a character in the show that we've seen for the first time in (one of) the first episode(s), and just went along with the show. He comes and goes, we don't recieve a lot of clues about him, but there is always something weird about 'that guy' and Patrick knows it aswell, but he just couldn't be sure. 

Brett Patridge is 'that guy', Heller knew from day one that he was RJ. I like it! Love the show.

Thanks for reading,
And sorry for my English. 

i dont think red john is just one person i think red john is everyone with the 3 dots i think red john stands for a cult or some sort of secret orginisation and not just one person

Whoa I think the lady who was feeding the pigeons on the bench in the premiere was at the visualize ceremony!

Pause the episode at 12:08 and you can see her. She has a silver watch or bracelet on. Do you guys think it's her?

http://www.youtube.com/watch?v=772FU_fAjj4  feeding pigeons


i don't have a link to her at the visualize meeting since it's not on the web much yet, but pause it after bret stiles yells "I PROMISE I WILL RETURN!" and it pans to show an applauding crowd. She is there.

Gale Bertram
Reed Smith
Thomas MacAllister

One of them is RedJohn. Bertram is the TOP choice. Especially because of the close mean look he gaves to Patrick. That look means "you got me bastard, I am so going to kill you now".
Enough theories. The stage is set. We finally got him.

I don't know who told to you all that it was personally RJ, who killed that girl in 6x5 episode, it would be really silly.
It could be anybody hired by RJ.

So the end of  6x6 was pretty predictable:
1. There should be several persons with dots on their shoulders
or
2. There should not be a single person with dots on their shoulders

There are 3 questions left for me:

1. Who and why blew up PJ's house ?
Another trick from PJ ? Really ? Do you think that RJ is an idiot ?
[sarcasm] First he would come for a cup of tea to Patrick's home with everybody from RJ's and PJ's list of suspects - oh there is no RJ, then lets blow up everything here, maybe he will think that we are all dead and will come for a cup of tea to CBI ?[/sarcasm]

2. Who survived ?
Actually it is obvious that PJ didn't kill anyone, just wondering.

3. Final question - how many persons with dots in Lisbon's team.
Rigsby and Van Pelt both have that tattoo or both haven't coz they saw each other naked.
Cho don't have dots i am sure.
Teresa obviosly have that tattoo (I'm sure, that this is the main secret of the end of the season, and we will see it soon) I will be very disappointed if i'm wrong

I'm sure, that we don't understand who RJ is. So no happy end this time, just a big question.