One of the biggest uses for YouTube is listening to music, and it's getting a bit more convenient to do that on Android today. YouTube Mix came to the desktop last year, but someone just threw the switch to enable it on Android. Simply search for an artists and rock out.

YouTube Mix is essentially an auto-generated playlist of an artist's most popular videos on YouTube. It seems to be mostly pulling up Vevo content for established acts, but the videos can be pulled from any account. After searching for an artist, the Mix collage should be shown at the top of the search results.
This is a server-side change, so you won't need to update your app to get Mix. We reached out to Google to make sure this is new, and indeed, it was enabled for Android very recently. Apparently users have been digging YouTube Mix on the desktop.