iTunes is both a mainstream juggernaut, destroying the competition in market and mind-share, and a great discovery tool, arguably just as good as any local indie record store. Often the store gets overlooked simply as a music store where people, who know what they want, go to buy their music. The strength of the iTunes store, however, is its ability to get you something new to listen to quickly. It provides a starting point in looking for new music, something that's mostly absent in Spotify and Pandora.
For example on iTunes, the new mainstream releases are highlighted each Tuesday in proper fashion with big banners and attractive graphics, but the rising stars are also given billboard space. Artists on the verge of enough name recognition to break into the 'mainstream internet' are featured along side the already engrained names, in the way a popular kid might say, You don't know this band, hmm, you should." It's music discovery disguised as subtle peer pressure. And that's an addictive drug.
Each genre landing page is stacked with style-appropriate artists, enough to keep the music enthusiast busy, but not too much to overwhelm novice. The 90 second song previews (for songs longer than 2:30) are nice. Not as perfect as the entire song, but, if we're being honest, plenty long to decide if the track is something you'd like to take home and get to know better. Also, did you also know there's a fairly new section titled 'New Artists'? Mixed in the list of different genres is a place dedicated to rising artists. Currently listed in the section are artists like Pacific Air, Churchill, Kitten, and Lord huron. You don't know those bands, hmm, you definitely should. Among the other details you might never notice is that all the artists they feature, including the ones under What we're listening to," are active artists, ones currently making music. Rarely do you run into bands that are dead ends which aligns with my belief that all discovery services need some sort of human curation.
Places for improvement, I wish the 'related artists' area was more filled out and able to keep someone trapped in a maze of new music. Once you've landed on a band you like, having that starting point and being able to expand from there and see who the band has played shows with, who sounds similar, and their musical inspirations could be pivotal in creating magical recommendations.
iTunes is far from perfect in a lot of aspects, but one of the most important parts in discovery, finding a place to start, is something the store does extremely well and a good reason to think of it as a music discovery service.