I just read the article about Credit Card Touch Payments on Japan trains and subways, but it didn’t mention Tokyo Metro Subway as being one of the lines that accepted credit cards to tap and pay at the turnstile.
We were in Tokyo in November, and traveled a couple of times between Ginza and Shibuya on the Ginza line and used the credit cards on our phones each time.
I don’t think I’m imagining that, but just to check - have any others used this on Metro lines in Tokyo?