In the New England area, I think Newbury Comics has done a good job of reinventing itself -- it wasn't ever (in my memory at least) just a comics store and made a lot of its money from music for a while, but if you go in there now it's got some movies, music, a comic section/room, but it's mostly other stuff -- merchandise from trendy games, shows, movies etc. Funny/quirky gifts, toys, jewelry, etc.

Maybe doesn't appeal to die hard comic book fans, but it's a fun experience for the casual shopper, which makes it viable. My 12 year old is always excited to stop in there.