Its a tough call between Strider, Infamous and Wolfenstein. I love them all for different reasons.
Strider is so damn polished and feels so damn fluid and ninja to control, even playing for a 10 minute stint. Infamous was much shorter than the two games before, but I still enjoyed swooping around town and causing chaos and watching how it all wrapped up that I played it twice through back-to-back and loved every bit of it. Wolfenstein is the shooter that embarrasses a lot of other shooters with its simple, bloody kinetic gunplay, and surprises by having characters and a world you actually want to get to know.
So yeah, its a tie between those three for me.