The real crux of the storyline was the vivid insight into Jane's past with his father and the further revelations of Cho's past with his father as well as his gang affiliation. Cho is definitely becoming a staunch ally of Jane, which in the end will certainly affect his attitude toward the capture of Red John. He is probably already of the mind that Red John should not be taken alive, but that remains to be seen.
The murder investigation was interesting in that the suspect pool was so large. As usual, Jane was pursuing his own assumptions(with a head injury nonetheless) while everyone else was going in the opposite direction. Cho was the only one that stuck with Jane and covered his back. Again, the Jane/Cho connection is likely to be a factor for the remainder of the season. Cho is haboring some intense anger and the murder of Bosco and his agents has provided fuel for the fire.
The tension is subtly being played out in the episodes following the massacre at CBI Headquarters. This makes "The Mentalist" a must watch for the remainder of the season.