(1) The Hipster Dilettante - These players are a cut above, if you don't mind them saying so - usually as they leave your Luddite campaign for something released yesterday. As GMs they are perpetually fluttering off to the latest trendsetting mechanics and settings, have a keen tendency to spend weeks or months preparing for a campaign that lasts all of one session.
(2) The Immersionist - These players want to be a part of the fantasy, and not just idle bystanders. They expect an almost religious attention to the smallest details, and woe betide the GM who hasn't exhaustively detailed the languages, religions and sanitary practices of their game world.
(3) The Tactical Wargamer - If it has hexmaps, strictly regulated LOS, and ammo tracking they'll play it. They don't do abstract, at all, so you'd better bring a Jane's Guide and drafting equipment to every game.
(4) The Thespian Storyteller - If it allows for cosplay, rubber swords and lengthy in-character soliloquys, they'll play it.
(5) The Snack Food Junky - If the gaming group supplies enough carbohydrates, they'll play it.
(6) The Soloist - If no other human being plays or even understands the game, they probably wrote it.
(7) The Freudian Slipster - If the game allows for revealing personal snowflakery, they'll play it.
(8) The Douchebag - If attractive members of the opposite sex play it, they'll use the game session as an opportunity to hook up.
(9) The Artiste - The write or draw a lot better than they game. Will spend much of the session either keeping a campaign journal in longform prose or sketching scenes for their graphic novel.
(10) The Senior Citizen - This guy was distantly or closely connected to some kind of Lake Geneva gaming group in the 70s but has done absolutely nothing in the intervening years. Will interrupt key moments in the game to tell an uninteresting, creepy and/or unfunny anecdote about something that happened in MAR Barker's basement.