Sure... But I'll use my MP3 player to do that. I don't think the PS3 will ever do that, don't think Sony wants to.
it's got nothing to do whether sony wants to do it or not, the ps3 can already do it. sony left it up to the devs to decide (and implement) if we can play our own music in their games. some games have been designed to let us do this since the beginning.