Well, basically, the type of music that would go along perfectly with the events that take place in the anime. Like, if you were put in the place to make a soundtrack for an anime, wich music would you think goes along best or relates with the storyline.
it depends on the anime and the events happening
sports anime like Slam Dunk, more upbeat music, especially rock,NOT heavy metal though, like some songs from B'z [Japanese rock group] would fit since they have quite a few songs that are related to sports, such as 'Go Fight Win',
also I have figured that many songs from B'z would fit into animes,especially the animes for guys
I am interested in writing music for movies and animes in the future.
oh man, here we go, ive been wantin to talk about this.... first off, anime music sucks, i love anime, ive been maga-ka for a decade, otaku for 2 decades, and if it is one thing that needs to change in anime its music.
like you guys have already pointed out, it just depends, but the opening and closing "music tracks" in most anime promts me to instantly fast forward to the first scene. its just full o' cheeze. i want to hear stuff like ambient, idm, industrial, death metal, psy/tech/and goa trance, drum and bass, dub, sonets, orchestral, cinamatic soundscapes, etc. maybe this will happen once ive got my degree in animation/directing