There's a pretty huge difference, unfortunately. I try not to be a snob about stuff like music, movies, etc so I stay open to things as they are as much as possible, but Greek myth is for some reason one of the things I really can't stand to see butchered. Anyone watch Immortals? As a gorey action flick, pretty good. As anything pertaining to Greek myth, total crap.
None of the gods acted like themselves, they had no personality, and it seemed like they just hired random models with no acting talent to sit and play around in some Hollywood fashion show-style costumes. Also, the original Zeus and most of the others don't give a damn about humans - they do whatever they please, so long as they don't act contrary to fate, and rarely ever find themselves deadset on helping humans for no reason. Instead, Zeus finds a way to Hollywood-it-up in this movie by giving dumb excuses for not helping, talking about how gods should "have faith in the mortals." If you're looking for a modern US butchering of Greek myth, Immorals is it.