Commercial will run the week of 16th this month.
As for the voices, I got word from the man himself.

The game will feature both English and Japanese voices as well as sub-titles for each langauge. He did this for the American gamer who enjoy both languages.

American version & Japanese version is 100% same.

We are sorry for our delay, and we hope you enjoy the game this month. This game is a great achievement for Team Ninja.

"Finn"

http://www.tecmogames.com/ubb/Forum27/HTML/000280.html

I was really glad when I heard about the dual languages. As a person who always uses the Japanese audio if it's a available, I really didn't want to have to deal with the English voices for this game. Especially after playing the demo. Ryu's voice wasn't too bad, but it was bad enough to make me wish I could've been listening to it in Japanese.

Of course, I can't say I'm too surprised by the dual languages. Team Ninja didn't even bother putting English voices on Dead or Alive 3.