In short it is about Japanese gangsters and beating up a bunch of people. There are good features that can quite get your attention like the customizing your own character, and this really reminds me a little bit of "Dynasty Warriors". you are by yourself and fight a whole bunch of people at the same time. Although here you can get help and have your friend join in to cooperate with your cause (whatever that might be).
Anyway, it looks good as preview, I like the song on the video too. Kenka Banchou 3 is schedule to be release on 1st quarter 2010. We'll see how it does