2011 was the year of streaming music for me--specifically using Rdio. Being able to follow what friends and folks I admire are listening to, easily listen along, and then build my own online collection in the cloud was a revelation. Being able to easily do it from my desktop at home, or at work, or on my mobile device for $5/month was just astounding. The world ain't perfect, but this is damn near close.
Anyhow, here's some of my favorite music from 2011, in no particular order ... a lot of which I probably wouldn't have listened to if it wasn't streamable on the Web. You might have to wait a few seconds while the YouTube clips load.