Seriously, nobody expected GGPO to work with the game, it has been pointed tons of times that GGPO only works with game that are not so resource consuming, so I never expected to see GGPO.
And about the arcade mode, meh, I'm sure that at this point japanese players had at least a PS3, or to a lesser extent, a 360, I'm sure that we will see them in console edition
EDIT: According to the professor from mmcafe, n° 17 wsa told by them that there will be some sort of patch to the japanese arcades