I like how people think motion blur is simply to "cover up" 30 fps. I play lots of games at 60fps with motion blur, usually dialed down a notch. It is an effect that happens in real life and doesn't happen within a game unless through a process.Now, many games handle it poorly, as in it being really strong or have a very low threshold before suddenly things start to smear. However, it is part of making a realistic game match real life so if done right, it can look great. Driveclub is an example of this.
Color filtering like Fallout 3 is pretty lame. I like the "corrected" version but I also think an in-between setup in the post-processing is nicer, as the artists intended to give the game the look it has. Battlefield 3 is an impressive looking game that also looks terrible at times in vanilla coloring. Yet, going with the "natural colors" looks interesting, but I like the style they have so again, would find a middle ground. That and get rid of the scattered "lens dust" etc. for that game.
Older post processing things that are still around today, like bloom in Wind Waker U, is gross and unfitting of that game's style to begin with. Finally, chromatic aberration is cool if done right, but this is almost never the case. GTA V does a decent job of it, and does channel separation in neat ways during certain moments (as well as weird filtering for being drunk or stoned).