According to the following post, the Vita's leader board lists 12,800 players. http://www.gamefaqs.com/boards/632918-blazblue-continuum-shift-extend/62736539
Can anyone else confirm?
If 100,000 are listed on leader boards, doesn't that mean they have logged in recently? Doesn't seem possible for the pc version. I rarely see more than 2-3 non-ranked lobbies.