NSFW aka Not Safe For Work is indeed the common nomenclature, but the NSFW tag is also useful for people who are accessing these forums at home with children around. Or for people who in general don't want to view NSFW items regardless of where they are and whomever else is watching.
Modern liberalism is based on the idea that reality is obligated to conform to one's beliefs because; "I have the right to believe whatever I want".
"Everything the State says is a lie, and everything it has it has stolen.
-Friedrich Nietzsche
"Every time something really bad happens, people cry out for safety, and the government answers by taking rights away from good people."
-Penn Jillette
A World Without Guns <- Great Read!
Frame for frame remake of the helicopter scene from The Matrix using video game models...
"The trouble with our liberal friends is not that they're ignorant, it's just that they know so much that isn’t so." Ronald Reagan
Yeah Team Fortress 2 and Left 4 Dead 2 don't have bullet models, just cartridges. Both games just display tracers. So they used what they had available.