This season finale was very well written and executed one from the cast & crew of Psych. May I say, this was the best one in the entire 3rd season.
Plotted along the lines of a bank robbery and an accompanying hostage situation, this episode did create both a racy storyline and gut-popping comedy track. Its definitely not easy to introduce some wise-ass jokes in between a serious situation and still make it look funny. But this finale episode did manage to do that, and successfully as well. As another interesting development, the writers have also put an end to the "Shawn-Jules: Will-they-Won't-they romantic tension", that has been lingering around since the "Bounty Hunters" episode.
A very recognizable trend which I've observed in the past few episodes, is that the writers are trying to focus on a non-critical character in each episode. In this perspective, the season finale definitely belonged to Lassitor. Overall, a good end to a seemingly average season. And definitely a lot to look for in the next.