Obviously the chances are exceedingly high that this will suck so badly that the entire area near the studio that puts together the final cut will be sucked into the miniature black hole created thereby. There are a few bright points that make one think it MIGHT actually be pulled off, however.
Perhaps the brightest of these points is the casting of Chow Yun-Fat as Kame-Senin. This is a man who's done some of the most badass characters in cinema, AND who's shown a strong sense of comedic timing as well. If anyone can carry off the simultaneously powerful and impressive, yet comedically ecchi Turtle Master, it's him.
While James Marsters is far from the first choice I'd have made to play Piccolo Daimao (my first choice, actually, was Wesley Snipes), the fact that Marsters is apparently a DBZ fanboy indicates that he at least does understand what the role is that he'll have to play, and might just not let anyone screw it up for him.
On the negative side, perhaps the worst indication is that -- at least so far -- they're still claiming an attempted 2008 release date. This indicates a SCREAMINGLY fast production effort, one that is in fact so deadly tight that I would have to assume it means that the rights to produce the movie expire at that point. This is a recipe for total disaster even with a much more straightforward production than DB/DBZ. Dragonball is a quirky property, one whose charm is NOT just based on the "Quien es mas MACHO?", but on the bizarre world that it exists in, and depicting all that -- with a terribly compressed production, special effects, and prep schedule -- is going to be one hell of a stretch.
Chatwin I just don't know enough about to be sure, but the fact that they're not even ATTEMPTING the trademark Saiyajin hair is not a good sign to me. Yes, it's possible the hair would be one of those things that just CAN'T be done well (though I doubt it, I know how I'd do it), but before committing one way or the other *I* would do a few screen tests both ways and show them to your MAIN target audience: fans.
Let's face it, a Dragonball movie is NOT likely to be a crossover-to-mainstream hit. You need to satisfy the main DBZ demographic, and that really means two things as an absolute, rock-bottom base requirement:
1) Make the combat Dragonball level -- which means something beyond anything yet shown on screen, something smooth, powerful, impressive, IMPOSSIBLE.
2) GET THE CHARACTERS RIGHT. Because what MAKES anyone care about the battles is the characters -- their appearances, their interactions, their relationships. Goku's physical appearance is part of who he is. It's a dangerous, dangerous move to think about changing that in a significant way.
It's clear that they're trying to find a way to make the movie as overall accessible as possible; this is a laudable goal, but possibly a self-defeating one. Some decisions I think are good (merging the role of Pilaf-sama with Piccolo, so that Piccolo is the sole bad guy, with Mai as his sidekick; without a chance to build up the basic whackiness of the world beforehand, Pilaf would be totally out of place), others... probably not so good. Particularly making Goku apparently a cross between Goku and his future son, Gohan, in that it *looks* to me like Goku is basically being placed in a role very similar to that of Gohan in the Great Saiyaman sequence. Goku's basic character is that of the innocent wildboy; putting him in high school is like bringing Mowgli to Beverly Hills 90210.
But we shall see.