Ugh. What a bad book adaptation. I think the people that wrote the screenplay skimmed the book and just threw the events together and hoped for the best. And they added plenty of "Hollywood Babble" to top it off. (you know "you saved my life, you gave me purpose, you completed me, etc")
The "evil" people were so laughably cartoonish. I adverted my eyes out of embarrassment rather than fear.
And then, my biggest complaint. They basically ignored my favorite character/plot line: Murtagh! He just kinda shows up, exudes Val Kilmer from Willow, and leaves. The elf girl takes over his role at parts. I was waiting for Saphira to break into "Can You Feel the Love Tonight?" We get it.
I did rather like their portrayal of Brom; in the book he seemed too much like Dumbledore from Harry Potter.
I was also very distracted by the fact that Eragon looked a lot like Mark Hamill. "Eragon, I am your dragon..."