I'm really excited about this kind of service. People have been moving increasingly online in everything they do, and music is no exception. I believe that in the future the vast majority of media consumption will use streaming. (As if it isn't, already!) My main side project involves this kind of service, so I know at the very least it can be complicated to write a server/website which can chomp diverse APIs. [1] What puzzles me is how this could be monetized--I'm sure YouTube and SoundCloud aren't in a hurry to stream their media for free without seeing license fees.

[1] https://github.com/fruchtose/muxamp