I think RJ is not Jane because in episoden 2x23 fake RJs have got Jane. RJ killed people who try coping RJ's work, saved Jane and told Jane a quote. It can't be Jane.If it is Jane it could be very big shock.
Red John seemed in 3x24. When Jane is sitting at the mall, somethings happened and Lisbon called Timoty Carter bla bla bla afterthat when Jane stood up, RJ walked away. RJ is near of Timoty who wearing RED sweater. When Timoty Carter was talking on the phone, looks like speaking to that guy. It might be RJ but Jane hasn't shaked hands. If it is gonna be crisis, we must know RJ now.
AND
It is very possible to be Brett Partridge but it will not be very big shock when we learn who is RJ. Lorelie said Jane you are just like RJ and really Brett and Jane's behaviors are similier.
