As far as I'm concerned this is all a rather stupid marketing ploy. It's particularly stupid after you consider the way music is made today.
A higher bit rate allows for a higher 'resolution' of sound. It allows for there to be more dynamics between loud and soft. This means that it will be easier to notice the little nuances played by an instrument or performer.
But none of that matters because of the way music is produced. Music is compressed beyond belief. Music producers compress tracks on songs hoping to make it sound better, or just because they think that everything needs to be compressed. Individual tracks get compressed. Groups of tracks get compressed. Then the whole mix might be compressed another once or twice. Music today is compressed beyond belief. Everything is just trying to be as loud as possible. No dynamic range.
Compression in music works by reducing the dynamic range. All the peaks you see on a wave form are chopped off making a more uniform signal, that signal is then boosted back up to as loud as possible thus reducing the dynamic range of the signal. Music today is quite literally made with reducing dynamic range as much as possible as a goal, nullifying a service who's major goal is to increase the bitrate / dynamic range of music.
I guess you have to ask the question, is this service going to make musicians start making better music? Increasing the dynamic range and bit rate of garbage music is just putting lipstick on a pig. But hey, some people like paying a premium for pig lip stick I guess.