One of YouTube's most popular uses is for playing music, so it's not surprising that Google is trying to beef up its performance when you search for popular tunes. Search for many artists on YouTube and you'll now see a Google Now-style card offering basic biographical information and suggested playlists, including entire albums and related artists.
As Google Operating System points out, the depth of information you get varies by artist. That said, I found basic pages for almost every artist I follow regularly. The 'Top Tracks' playlist is certainly handy if you feel like binging on a particular artist, though ads will pop up randomly while you're doing so.
YouTube Music Cards [Google Operating System]