I know, it will likely suck, but I'll end up watching it anyway.
At least several of the actors are actually fighters, some of which are proficient at the style of the character.
It turns out it deviates a lot from the plot from the games, and characters have been altered heavily.
Anna and Nina don't hate each other. {click spoiler in first post for proof}
Bryan has never won a tournament in the games, yet in the movie he is a champion.
There is no Devil Gene whatsoever in the movie, changing Kazuya and Jin.
Jin is more rebellious than he was in any of the games, including Tekken 3.
More information:
Tekken (film) - Wikipedia, the free encyclopedia
It also has characters who don't fit in because of alterations made.
Example: Miguel didn't get involved in the tournament until after Jin became the champion and took over the Mishima Zaibatsu, so Miguel would have no place yet.