The third season of Lie to Me was…still good. That said, as much as I liked the acting and the whole concept of the show, it became a little bit tiring. You can only see so many variations of the same theme before you want something else. My favorite TV-show-format is one that does long-format stories (one season or more) partitioned into mostly self-contained stories, which admittedly is the hardest thing to do. Either you get the mix of long-form and mostly self-contained stories (X-Files, StarGate and others come to mind) or long-form stories with no real breaks, where each episode ends on a cliffhanger.
Episodic shows like Lie to Me though, while working well for a season or two, always get boring sooner or later due to their static nature.