As a recent rule of thumb, I'd say to watch out for those roller-coaster rides---make sure (by asking) if they did a nondestructive test on the wheel shafts to the coasters (had a fatal accident last May in Japan cause they didn't do that test!).
Also, I did hear about the spas being a bit too unsanitary for CF'rs. I'd just recommend showering before and after going into the pools, spas, etc. for preventiion...however, things must be different for the "spas" in Japan, where I'm not at all concerned about going in there...unless another Yakuza gang shows up, again!!