With the addition of the "check out people's spec" feature in 2.3, I found myself spending a lot of time looking at other people's specs. One thing I noticed in a staggeringly vast majority of players is that they don't spec into their +crit % talent. (ie. Malice for rogues, Cruelty for warriors, Lethal Shots for hunters, etc.) From my knowledge, these talents are, or used to be considered invaluable.
Realize that I'm not just talking about your average player who skips these talents. People who I pegged for the WoW elite theorycrafters were doing this. I can't make sense of it.