We bought this film in a two-pack with PoE and find ourselves watching King of Dreams much more than PoE. I personally find that:
1) The story is incredibly satisfying emotionally. Joseph's story of commitment to God in the face of such challenges and especially his struggle to forgive his brothers is something that I think everyone can relate to.
2) The acting is top notch. They didn't near as many high powered stars as PoE, but apparently Ben Affleck and Mark Hamil decided that they couldn't coast through this and put in super performances.
3) The music is less "soundtracky" and more singable. I 2 years later, I still can't get "You know better than I" out of my head.
4) The animation, sigh, is not quite as ambitious as PoE, but is definitely sufficient to tell the story. I didn't notice any letdown until I read a previous poster's comment about a lack of animation on the level of the Red Sea parting or burning bush PoE scenes, and they're right. But I didn't miss them. Go hang your PS3 screenshots in a museum -- I'll stick to my awesome Wii gameplay.