Most people advocating for a Wii port just assume the game is going to play well - there's absolutely no guarantee of this. Port of arcade games to inferior hardware have rarely resulted in games that completely resmble the original and usually have some frame-rate/slowdown issues that plague the game and make it unplayable to the more dedicated audience. It will be an imperfect game - so essentially, people that play fighting games (a market that you want to target for a fighting game) are likely going to opt for the 360 or PS3 version. That demographic most likely already has a PS3 or 360 - other big name fighing franchises being released on both console already has established that market on both of those systems.
The Wii has not shown it can support a traditional fighter, and while some third party games have done remarkably well on the system it's still a mixed bag for developers. TvC was the traditional fighter built on Wii hardware that was released on the Wii and sold about 100k in Japan. With a Tekken 6 Wii port, Namco would essentially be trying to sell a watered-down Wii version when a superior version is readily available on the PS3/360. There market for that audience probably is too big. The fighting game community is going to shun a Wii port regardless because they're jerks (and a lot of them already have a PS3/360 because of SFIV). Anybody that likes to think they are good (there are a lot of these people) are going to get a 360/PS3 version too. Anybody that wants to play their fighting games online is going to get the 360/PS3 version - those online interfaces are bound to better than the Wii's. Anybody that owns both a Wii and another console will most likely opt to get the 360/PS3 - it will definitely look better and is bound to get heralded as the superior version by media and most everybody else that touches the game. I just don't think the market that is left is large enough to justify a port. I mean, even most of the people defending a port wouldn't get a Wii version. And the people here defending Namco for not making a port definitely aren't going to get the Wii version either. The audience just isn't there.
i'll go play blazblue now










