I'm doing a review of this movie mainly because I felt that the one-star rating given to the regular DVD version is pretty cruel. If you look at the Rotten Tomatoes film rating site, Defiance gets about a 56% rating over there, and I think that's fairly accurate.
The problem with Defiance is that there isn't really any story, or at least any story arc. All these people go into hiding in the forest, they have very minimal adventures there, and at the end... at the climax after the big battle scene... they're still hiding in the forest. There's no "escape from alcatraz" moment when everything comes to a head... although I guess the final battle scene was meant to be that type of moment (if so it doesn't work).
So Craig and Schreiber are fine in the lead roles, but despite the intended tension and rivalry between their characters, their relationship seems kind of flat as well.
All in all... this movie is weak, but it isn't as terrible as the one star rating mentioned above.