It has been confirmed that there will be no disc update. People saying they are going to be waiting for super SFxTekken are going to be waiting a literal eternity.
http://www.joystiq.com/2011/11/12/ono-sfxtekken-uses-new-netcode-dont-expect-a-super-version/
Edit: Of course Ono could be trolling but I think they realized that its more profitable for them just to do DLC. No need to press, package and ship discs if your game can support DLC.
http://www.joystiq.com/2011/11/12/ono-sfxtekken-uses-new-netcode-dont-expect-a-super-version/
We recommend filing this one under "Things to take with a grain of salt" in your PR filing cabinet, but Capcom veteran and long-time Street Fighter producer Yoshinori Ono has told Gematsu that there will be no boxed versions of any future Street Fighter X Tekken updates: "I would say that you don't really need to worry about a new version of the game coming out. If we choose to update the game, it will be done in the same fashion as Street Fighter IV: Arcade Edition."
Edit: Of course Ono could be trolling but I think they realized that its more profitable for them just to do DLC. No need to press, package and ship discs if your game can support DLC.