My first impression of Ark is that it was at least in part inspired by the video game series Final Fantasy. The breathtaking scope of the domed city to the design of the movies villain and most of that character's and other's clothing all reminded me of Final Fantasy. Even the animation is similar to Final Fantasy: The Spirits Within although not as realistic looking. The story is good and there is almost no end to the parallels that can be drawn between the movie and situations in the real world. Where Ark falters is with the voice acting. James Woods is the only recognisable name in the credits and most of the characters dialogue seems flat and unemotional or over acted.
I'm giving Ark a 6 because I don't think it would stand up to repeated viewings. If you like Final Fantasy or enjoy animated films that aren't just for kids Ark is worth a look.