It mean Quick What the Fuck. Kinda like WTF but a little diffrent...and quick-er
QWTF is that? Is that your mom? Whats she doing with that hot dog and a german shepard?
QuakeWorld Team Fortress
The original Fortress mod of quake
The team went over to valve and wrote TFC for the halflife engine
QWTF was the best version of this mod and probably always will be
QWTF ROX MAH SOX!
QWTF is the original and best version as TFC (spit) sux