Cel-Shading games are more arty and cartoon like in which they are presented usually they are on consoles like the Wii and the XBOX. Examples of this are: XIII for the Xbox and Super Paper Mario for the Wii.
Abstraction is giving the games an unrealistic feel and therefore feel different when you play them, usually these games come out on the handheld consoles and some home consoles. Examples of thiese are: Patapon and Lemmings for PSP.
Exaggeration is like Photorealism, but the people's facial features are exaggerated and the game play is more adventure type and quest like games like the Final Fantasy 13 for Xbox 360. They're also featured in beat 'em ups like BlazBlue for the Xbox 360 and handheld consoles Scribblenauts on the Nintendo DS where your character has a square head with eyes very far apart.