I'm satisfied with the guilty verdict as I do believe Jonchuck is mentally ill but was not insane when he dropped Phoebe, who was terrified of water, off a 60 foot bridge to her death. I might have paused if he had claimed that Phoebe was a demon or that God told him to murder her but he did neither.
Hours before he murdered Phoebe he said "If I can't have her no one will." Those aren't the words of an insane person, they're the words of a vindictive, grudge-holding sociopath. He did to Phoebe what he did to his computer when he was told he had to use it to obtain his GED and not just play games on it - he threw it over the balcony where it was smashed beyond use. If he couldn't have his way then no one would be able to use it.
IMO he'll appeal the verdict and IMO he'll lose. Rest well Phoebe, he'll never hurt another child.