There's really no incentive to sign up for this that I can see....it costs the exact same as Spotify and it sounds like it doesn't even have the student/family discount.
Not to mention that you can get 3 months of Spotify for .99.
Maybe it will have some kind of system integration to make it worthwhile...we'll see.
Apple might be able to offer up a larger catalog of music than anyone else...The Beatles, Taylor Swift, Radiohead, AC/DC etc..