Honestly the dual screen attracts me more to the DS, than the ability to play music or watch movies to the PSP on a games console. I already have a MP3 player, and I think the idea of going out and watching a movie is stupid. Watch a DVD at home or go to the cinema.
Additionally graphics don't interest me that much as I'd prefer innovative, fun games to highly graphical games played the same way as other consoles do.
However you should buy the console with the games on it that you want to play, so with the fact that the PSP is going to attract the big name games to it, I'd probably pick one up in the future, when it's come down in price.