This topic certainly isn't new but I would still like to bring it into light.
Honestly, if SG won't be released in Japan, then I won't be pursuing the game anymore(I bought the game). Any good fighting game being kept away from one of the most prominent FGCs simply isn't right. Besides the gameplay, SG features excellent sex appeal =D as well as having the slickest animation in a fighting game. There has got to be an audience in Japan for that!
There hasn't been much news from Reverge Labs concerning Japan so I'm just assuming that there hasn't been a conscious enough effort to promote it there, not to say that they aren't hardworking folks. Reverge Labs, you have two thumbs up from all of us! :)
If Japan does get ahold of SG, I have no doubt that the game will grow in popularity, not to mention its place in tournaments. I guess we'll just have to see once the updates and dlc are out in the rest of the world. Japan isn't a big proponent of digital releases, but that isn't the problem.