Nega-me would be an ignorant liberal with no work ethic, an irrational pity/empathy for the lazy and stupid, a completely fuck ass backwards view on the world, and use uninformed opinions as factual arguments. So far, this is pretty much describes a typical democrat, so I'll get to more specific things. They would:
Have no respect for the need of good stories in games
Consider a critic's opinion on a game a legitimate reflection of how good is actually is
When judging games themselves, only factor graphics and gameplay into their decision
Be unwilling to accept change in a series, even if the resulting game is absolutely amazing (i.e. they would hate FFXIII)
Deny that there are any good games outside of this generation of consoles, and subsequently deny the fact that the PS2 (combined with PS1 backwards compatibility) has the best library of games ever.
Have god awful taste in (and even definition of) music (i.e. they like rap)
Be obsessed with sports
Buy terrible casual games that are killing/have killed the game industry, which includes buying the same shitty sports game year after year when hardly anything has changed between them in the past decade.
Be a complete dick to everyone around them by being obnoxious for the sake of it, and trying to convince people that he's the smartest/nicest/talented person they know.
Judge things based on their classification rather than their content
Denies God, tries convert people to his religion using insults/threats, won't stand for anyone being a different religion than him.
I'm sure there's more, but that's all I can think of right now. Individually, these are obnoxious and annoying, but when they start stacking up, they quickly become enraging and infuriating. If I ever happened upon an individual with all of these attributes, God help him.