Well regarding the music player.
All i ever basicly do is set the setting on repeat, and listen to the same song like 4-5 times and just change song, i dont have different playlists of certains songs either.

And as long as it's battery can life a good while ( maybe close to as much as on the iphone while listening to music? if i'm not wrong they did say they wanted the Nokia n900 to be able to last a very long time while using lots of things at the same time)

And the gps, i dont intend to use it as a gps for navigating a car from one country to another, it's usualy just to see where a certain street might be in a town or in what direction'ish, nothing big and fancy either.

And in the end, i am also thinking about keeping my iphone as an mp3 player or something, like, have the iphone for music, videos, and games, and the nokia n900 for the other stuff

EDIT:

I mean one of the bigger things that is a factor when i buy a new phone is "Do i like the design and feeling it gives off or not?"
i mean i mostly just use all the basic stuff that most phones can do, but want it to be appealing and handy/functional ( and like i said, all those ugly *** sony erricson variants of a model are ugly, althou their X10 looks nice, but never really got the big thing about the android OS :-/ )