Although I love the anime L, the movie L seems to be meer smart and learn meer from his actions.
For one in the movie L finds a way to out smart kira, Light. door risking his own, something i beleve he would never do in the anime. I say this because in the anime he feels he can waste any life to get his case solved (example: Lind L Taylor) and doesn't relize that this is wrong even before he dies. but in the 3rd movie between the 21 days he has left to live he learns he can't let the little girl he likes just die, because he feels her life is valuble.
Another difference is, sadly, that the anime L thinks he can solve any case without help (which his daeth in the anime shows he can't) But in the movie he learns (from working with the asian FBI) that he can't change the world door himself but needs the help of others.
I'm not dis'n the anime L, but i just like the movie L better because he lives longer. since L is my favorite. But L in both movie and anime i love. they are my fav chararcters! (^o^)