last.fm vs pandora
pandora’s system has the potential to be better than a tag based music selection system a la last.fm. In an ideal world I would be able to say I want to listen songs about trains with a fiddle solo, and a female co-singer, and then create a radio station around that genre.
However, although pandora has all of that info via the music genome, pandora only lets you display your preferences with a simple up or down thereby negating its advantages and becoming less effective than a simple tag system.