The game clearly states "Worldwide netplay" on like... every single company website and packaging scan available. How often has anyone seen region-locked online play?
The Blog update from this very week even says we have the option to select a region filter, right? Why would anyone think the online play would be region locked?!?
The only thing that could be region locked is the game disk itself (and mostly on 360, since most PS3 games are region free.)
The game itself being region locked to consoles of different regions, wouldn't be too suprising though. Especially if each region had some specific translation work done, or if they just want to keep members of each region from trying to buy other regions editions, to get foreign preorder /special edition bonuses. But we won't know details on that until release, or near it.
I can't think of one fighter I've played this generation... or even the last one, really, that had region locked online play. I remember lagging with the Japanese players on DOA, screaming in horror at foreign play on Hyper Fightings atrocious netcode, being fairly impressed with them on HD Remix, and meeting people from all areas of the world on NGBC and 2K2UM online...