And these platforms are becoming increasiingly interconnected with many other websites you use daily. Ticketmaster, Spotify, CD Baby, and eBay have either already integrated ot plan on full integration into Facebook. Youtube just added a "buy it now" button for songs wo work with Google Music. All of Apple's products are designed for integration.
In order to survive as a musician in the digital world, you need to make your music compatible (available) with these big four platforms (not that big four, sorry). Most all internet traffic will be centered around these behemoths and if fans cannot get your music here, you'll either be pirated or worse, ignored.
How important is it to be on the "operating system" as your fans?
Magazines have been reluctantly making the transition to digital subscriptions for years, but with low renewal rates and slow growth, it was not as profitible a channel as it could be. When Apple released the Newsstand icon as a default on the iPhone and iPad, sales of digital subscriptions went through the roof.
PixelMags reported a 1,150 percent growth increase in the first week after Newsstand and iOS 5 debuted on Oct. 12. It’s now sold over four million digital magazines.Why? Digital magazines finally aligned with the same platform that fan's were using. The Newsstand app moved magazines from being buried behind apps, to being front and center on the home screen. The product stayed the same, only the platform changed.
New music/tech websites form and disppear every day. Some will grow large, but most won't. A majority of your online sales will come from major platforms, as that's where most of your customers spend their time.
Make sure you're available on the same "operating system" as your fans.