Ok that does it I am just going to post the list.

1. In the movie if a rider dies his/her dragon dies in the books this is not the case. (Brisingr pg 636-637)
2. the love interest with Arya is completely different from the one in the book where Eragon is spurned by Arya.
3. Urgals are part of the empires military forces in the film not controlled by Durzza as in the book
4. Hrothgar the dwarf king dosen't exist neither does Orik
5. Eragon is much stronger than Arya in the film where in the book he is clearly outmatched by her.
6. There don't seem to be any dwarves in the film as all of the people in farthen dur are of the same height.
7. The Twins don't exist
8. Farthen dur is easily accessible to dragons as saphira flies out of the crater in the film where as in the book the hole in the mountainn is too high for even dragons to reach.
9. Sloan seems to like eragon in the film he knows the egg is the king's propetry and tells him to hide it.
10. Sloan is tortured and killed in the movie
11. The Ra'zac die
12. Katrina dosen't exist
13. Brom believes he is responsible for there being only one dragon in Alagaesia
14. The foresworn don't exist
15. The geography is wrong in the film daret is near foothills of the Beor mountains instead of being in the northen reaches of the empire .
16. Surda dosen't seem to exist.
17. Saphira has to obey eragon in the film where as in the book she dosen't and stays by him because of their bond. (eragon pg 157)
18. Saphira has a different personality
19. No evidence of elves existing
20. Jeod dosen't exist
21. Horst role is cut to the mention of his name only once in the film.
22. No werecat or werecat prophecy and angela is met in daret which isn't on a plain as in the book but in a marsh.
23. No star rose
24. We don't know where Roran has gone so it is likely that if there is a second film roran's plot will be dropped and he will just show up at the varden.
25. In the film the varden are not aware of Brom or that he never played an important part in their councils.
26. Arya refers to Eragon as the leader of the resistance in the film where as in the book he swears fealty to the Vardens new leader Nasuada.
27. In the film it seems that there are only two dragons left saphira and shruikan no other eggs so no thorn.
28. Magic seems completely different from the book
29. In the film it says dragons are the source of magic in the books oromis says that magic exists in nature without riders or dragons.
30. In the film galbatorix wants to kill eragon where as in the books he wants to capture saphira.
31.Eragon already knows the Arya is a princess (very minor)
32. Film misses training of Eragon by Brom to be a rider could have been done in a two or three minute scene.
33. In film brom is killed by durzza not the Ra'zac
34. Murtagh dosen't shoot the shade or save eragon from the Ra'zac
35. In the film saphira instantly grows where in the book she gradually grows.
36. Saphira can't breath fire until after she breaks the star rose in the book but in the films she can breath fire from the beginning.
37. Eragon's power when he first uses magic is vastly incrased from when he used magic in the books.
38. Arya has the wrong hair color and isn't an elf (as these don't seem to exist also she dosen't have pointy ears.
39. Eragon dosen't injure his legs or rely of Saphira for warmth after their first flight.
40. Hadarac desert isn't mentioned and probably dosen't exist in the film world because of the other geographical mishaps.
41. Eragon isn't going to Ellesmera at the end of the film with Arya so will he get any additional training and do Oromis and Glaedr exist it.
42. Elva dosen't exist
43. Doesn't seem that Arya can use magic do the same degree she can in the books

That pretty much sums it up as if anyone comes up with new reasons I add them to the list.

1.arya wasn't asleep when eragon and murtagh fleed gil'ead.
2.urgals didn't have horns.

It's a list I made in about an half-an-hour one day when I was really bored. I just post whenever something like this comes up and it really shouldn't do as these kind of topics have been made before...

also the mark on eragons hand is differant
silver palm not a weird looking "e"

A continuation of E+A's list:

Brom died in the wrong place and differently.
I don't remember the diamond tomb.
Eragon found out about Brom being a rider too soon.
There were no traders in Carvahall.
There were already soldiers.
I don't remember SOlembaum.
No sign of Oromis.
Elva wasn't in it.
Star Rose didn't exist.
Arya leaves without Eragon in the end.
Jeod wasn't in it.
Galbatorix is in the movie.
Saphira had feathers.
Saphira was obedient.

Well it gives several descritpions about how her wings are and dragons are not birds. Scales and feathers just don't mix.

they killed one of the ra'zac thats not suposed to happen

*sits here and wonders, "Why the heck did I make this topic? Legendary Failure."*

MOVIE ONE HAD NO MISTAKES IN IT....
OTHER THAN THIS:

THE MOVIE ITSELF!!!!!!! DER!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

**Sorry, my spoiler thing for BBC wasn't working. IDK why...