Always stand on the left side when taking an escalator in Japan so that those who are in a rush can walk on the other side. Time is of the essence! So is good manners and basic courtesy.
However, do stand on the right side when you are in Osaka!
Here? We stand any which way we like. I am rather partial in standing in the middle myself. But that's only when Zaini and Raimie are in front of me. xD
p.s have you seen SK's awesomely packed escalator photo in his previous post? I wish I had photos like that!