Personally, I find proactively hunting for new music tedious: plowing through a bunch of rejects for an occasional yes. What seems to work better for me is reactive hunting, meaning I hear something on a commercial or in a show or movie, one of my friends or family suggests (or is playing) something (when I'm around), or I pick up a used copy of Now that What I call Music Volume XX and find a few goodies there.
I've built up a fair collection of owned music over the years. I've made multi-hundred song playlists of these faves and often fill my music-listening time by just shuffling those songs. I'd love to find lots of great new music on par with some of that but it's hard to find great new music IMO. Much of the new seems no so great IMO... not worthy of allocating a few MB on a hard drive to retain them. I don't see how this service or Spotify or Pandora will solve that problem, as I don't want to just put any of them on and listen through the bad for something good.
An interesting divergence of views might be observed here. Over in some other threads, "we" are whining to get rid of 185 channels "I never watch" because "I only want to pay for what I do like." We have all kinds of rationale why we don't want junk pushed upon us and we certainly don't want to pay for that junk. Then, over here in streaming music threads, we are dying for streaming radio so that we can have undiscovered music pushed upon us and we do want to pay for it. Since I know not all of that will be great, I find it interesting how the same pool of people can have such differing views of almost the same thing.
I haven't found a source of streaming or otherwise that only push great new music to me. Instead, it's a bunch of junk (IMO) to find an occasional good one... much like those 185 TV channels can be a bunch of junk but occasionally have something I might want to watch. Conceptually, a "top 40" channel is supposed to have the best new 40 songs available. I hardly ever hear one in such streams that I consider a "keeper." If my general tastes like that are representative of many, I don't think streaming "is the future" in terms of solving a problem of music sales or ongoing monetization of music. Instead, I think the answer is the harder solution of finding the next Beatles, Stones, Zep, et all and bringing them to market... lots of them if lots of them are out there waiting to be discovered, packaged and marketed.