Most likely the US version of the game will be region free. It is that way on a lot of games. e.g. I bought a copy of my Bioshock (US 360 ver.) to play on my JP 360. I'm looking at picking up COD4 (US 360 ver.) to play on my JP 360. I'd pre-order GTAIV for the 360 (US ver.), but I'm waiting to see if it will be region free or not.
http://www.play-asia.com/paOS-19-49-en-15-%5C%22Grand+Theft+Auto+IV%5C%22.html
Usually, they test games for each regions consoles to see if they work or not.

starcraft: "I and every PS3 fanboy alive are waiting for Versus more than FFXIII.
Me since the games were revealed, the fanboys since E3." 


Skeeuk: "playstation 3 is the ultimate in gaming acceleration" 









