• Shun Akiyama: A well-dressed loan shark who was once a homeless. In the trailer, Shun was seen sitting around with a bunch of other homelesses, and he explains that he lends his money to people with moral faith.
• Masayoshi Tanimura: A young, slick looking detective in Kamurocho. The trailer showed him playing mahjong, and then the scene switched to a back alley where he's accepting bribe money in turn for looking the other way. It turns out that he's a corrupt cop called "The tick of Kamurocho".
• Taiga Saejima: A huge muscular man who's escaped from prison after killing over a dozen Yakuza members. In the trailer, he goes on a bloody rampage with revolvers in both hands, killing everyone inside a small Japanese restaurant. After unloading both, he switches in another revolver clenched in his mouth, and empties that into his enemies too.

Yakuza 4 is scheduled for a spring 2010 release in Japan. No western release plans have been announced.

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• Yakuza 3 headed to the West, Yakuza 4 announcement incoming
  

Via Gamespot