Online music and video distribution channels have helped the independent artists insanely. Same goes for online books, apps, etc. It's never been easier and more profitable for an artist to get his name out there, and even more important: he's not filling the pockets of some corporate suit while he can barely pay his rent.
Standard cut on most online distribution schemes is 70% for artist, 30% for vendor. You may find that as a "well, all Apple/Amazon/etc does is provide the download and the transaction server, they don't deserve that much!".
Look into what a major label takes from the artist. You'd be shocked. In the heyday of traditional physical media, it was not uncommon to see bands in the top 20 barely able to pay rent, while the music conglomerates drank vintage wine off the bands album sales.
Ask anyone who was ever in the music industry can tell you how the labels screwed you in old media days, before it became an option for a guy singing cover songs while strumming a guitar to "release an album" via online vendors. Online music stores have become a revolution for smaller artists - artists that otherwise wouldn't have stood a hope in hell of getting past the "mixtapes" and "check out my MySpace band page" phase.
2012 will be the first year that online sales will surpass hard copy DVD sales, a stated fact predicted by the industry. It's a trend that is here to stay, and something old media are fighting tooth and nail to not give up. Frankly, they have no options. While some people live for physical copies for media, 95% of the rest of the world doesn't. We want it quick and we want it now. I can buy any album I like online now, and enjoying punk music, I can't generally just stroll into a record store and buy the latest UK Subs album. I can online, and have said album here for $9.99 within 2 minutes, ready to listen to, and even preview tracks before I buy, or buy individual tracks. As a guy who has well over 1000 vinyl records, it was hard to get used to for me.
As for being locked in to anything - don't buy DRM media products and it's no problem. Everything I have on my Apple products is on my Android products. I'm not locked down to anything.