Its launch may have slipped a few times but DoA 4's release is now imminent in the US and looks to be out early Febuary over here. IGN have their review up which you can read here.

At first glance, Dead or Alive 4 might seem like more of the same...with better graphics. The visuals comprise relatively similar looking characters heightened in detail with backgrounds that will make you look twice. But graphics don't a fighting game make. The Dead Or Alive series always has been criticized for its simplistic counter system and lack of depth. Dead Or Alive Ultimate was adept at taking the game online, but didn't provide the long-term fighting experience for which gamers were hungry. Dead or Alive 4 addresses every issue thrown at the previous iterations in the series with varying degrees of success, tackling everything from the counter system to cancels, the ground game, blocks, and interactions with the environment.

But once you get past the button-mashing phase and are finished enjoying the novelty of having a new Xbox 360 game, you'll find the game has changed pretty significantly.

There are also some high quality videos over at xboxyde, they're links are fast but not always working! So try again later if they are down at the moment.