I guess in the wake of Lord of the Rings and The Lion, the Witch and the Wardrobe film makers felt they should take every last fantasy story and fast track it to the big screen. There can be no other explanation for Eragon, a film that feels rushed, sloppy and laking in any sense of fantasy.
Supposedly fans of the novel were quite disappointed with this adaptation. As someone who has never read the book, I can only image how the story played out in text. It's not a very interesting one to say the least. I understand the novel was written by a teenager, certainly a smart one, but still not a literary giant. The story rips off every fantasy cliche there is. A big part of the problem with Eragon is the story is so predictable and uninspired.
The rest of the problem is how cheaply it seem put together. The reason Narnia and Rings worked is how much the film makers loved their subject and nurtured the creation of a tribute film. Eragon feels mass produced, with all the corners cut and no heart.
I guess if you are a fan of the novel you will be disappointed. As a new comer to the tale I was also left cold. Unless you are dying for a tale about a dragon, step over this little mess.