Pulling a dick move is engaging in an egregious, selfish and usually public stunt, i.e. a cock-block or dumping a workload unnecessarily upon a friend or coworker. The exclamation of the phrase "Dick move!" in a high, nasal voice is sometimes the only socially acceptable recourse. Other common reactions include "Shenanigans!", "Bullshit!" and, a personal favourite, "BULLSHIT SHENANIGANS!".
John likes Cindy. Erik likes Cindy. Erik and John are friends. Erik intentionally keeps Cindy busy at a party ("cock-blocks" John). John finds out about it after the fact, and yells "Dick move!" Given the nature of their friendship, violence may or may not occur.
N: An act that is seen as mean, or negative; That was a real dick move!
There can be multiple levels of a dick move. Level one is something minor and insignificant (i.e: Like throwing someone's external HD into the bathtub). Level two is something like that asshole in charge of the Titanic who let it sink, and level three is on par with 9/11.
Some argue that the Holocaust was a Level 4 dick move, but others argue that is was just plain a shitty thing to do.
Guy: Dammit, Osama!
Other Guy: Yeah, that was a real dick move, that whole 9/11 thing was.