I remember at E3 2005 Itagaki said DOA4 was at 15%, then half a year later the game was out. Granted DOA5 is a much bigger step forward than DOA4 was, but they also have a bigger studio now and plenty of experience with the consoles. On top of that fighting games have relatively short development cycles in general. Honestly I wouldn't be surprised if DOA5 released Fall 2012. 
As for Team Ninja taking input, eh... I don't know about that. PR people love talking about how they care about what the community thinks and how they're always taking input. I especially love it when a beta gets released, many people complain about certain things, and nothing changes in the final build