Remember it's called Virtual Console, not Arcade.
They are only releasing straight-up console versions of games. Nintendo stated online capability will not be added to any VC games. Also, you'll never see arcade ports on there. The version of SFII: World Warrior that was recently released was the SNES version. Nintendo places a lot less emphasis with online gaming than Microsoft does, so I doubt that if a MK game gets put on the service (the best bet would be MKII for the SNES), they'd hack it open and add online. Nintendo just doesn't care about online enough.