Me? Shooters. Bulletin board 2ch has a thread up (translated by game localizer and Yokai Attack author Matt Alt) asking gamers what they play in arcades. Here are some of the replies:
-"Games that even beginners can easily start playing have really been on the decline recently."
-"Tetris or PuyoPuyo."
-"I was super into Time Crisis for a while."
- "QMA with a friend."
-"Damn you otakki bastards who play QMA alone while taking notes! It's a game for couples!"
-"Fighting games or QMA."
-"Ones where you kill zombies."
- (Absurdly detailed thesis about PuyoPuyo)
- "Whenever my friends and I go to the game center we basically stand around for a while and leave because there isn't anything a beginner can just start playing."