Even then some games require a bit of alteration. Sure you can get a good all-around setting, but there is plenty to optimize for specific titles to handle different lighting and glow. I typically optimize for a couple titles, and just deal with the rest as it's usually pretty good for those.
Don't even need to buy a calibration DVD, http://www.youtube.com/watch?v=qG0Xgpqk7EY
_________________________________
In the end, it all depends on your visual preference. I tend to have a bit of color blindness so I set colors a tad less saturated than than what most, but turn the contrast up higher for example.