NationStates/YMMV

Regarding the game itself:

 * Broken Base: This is probably the best way to describe the multitude of divisions of fans and the subdivisions of these divisions.
 * Catharsis Factor: One of the reasons the game is addictive.
 * Dude Not Funny: Some people reacted this way to the 2011 April Fools' joke, which involved setting people's accounts up to look like they had been hacked.
 * Good Bad Bugs: A very common one, in the form of (example): "This raises an interesting issue," says Elizabeth Winters, your brother.
 * True Neutral: When your nation is categorized as a "Inoffensive Centrist Democracy". (it's in the middle when it comes to personal, political, and economic freedoms)

Regarding the roleplaying section of the game:

 * Ass Pull: Surprisingly fitting trope to start with.
 * Complete Monster: National leaders and notorious criminals alike.
 * Even Evil Has Standards: Murray the Evil Skull. He even calls this trope by name. That said, though, the only really evil things he does are put curses on people and sing country music.
 * Leeroy Jenkins: The Ryou Black Islands and all his previous incarnations.
 * Magnificent Bastard: The forum moderators are equal parts respected and hated.
 * Memetic Badass: Some of the older and more respected roleplayers are this.
 * On the General (ie off-topic) forum, Lunatic Goofballs has been practically deified. The mods responded by making him a mod.
 * Nightmare Fuel: Some people have written sufficiently grim threads to make readers feel physically ill.
 * What. The. Hell.
 * Stop Having Fun Guys: A recurring issue over just about every kind of role playing you can imagine, but most often seen from players who yell at people using Rule of Cool things.

Regarding Forum 7, the casual off-topic place:

 * Memetic Molester: Grittonia, but he is loved all the more for it.