In case anyone else is interested, I stumbled on a nice little arcade yesterday. It had all the staples, drumming and dancing games, racing cabs, fishing games, Tekken 6 and SF4 Viewlix type things etc. Then on my way out I notice a smaller room in the corner, took a quick peek and found a room full of Sega Blast City cabs!
If you take the line 1 subway to Xidan and exit the station at exit A, walk north a few metres and there's a little underground mall with a sign outside for a science museum. It's in there. Will go back sometime in the near future and take better pics and play some DDP!