I’m guessing some people have userscripts to update? 
Some changes I noticed:
On artist and album pages, the tabbed interface with multiple sub-pages (one for biography, one for discography, etc.) has been replaced with a single page that has collapsible “windowshade” sections with dynamically loaded content. Metadata that used to be sidebar content is now near the top of the page. The high-res album art is still accessible.
Some artists and albums now have iTunes and/or Spotify links. Unlike the Spotify links for tracks, these have the artist/album ID, not just a search string. As before, Amazon links don’t have ASINs; they just perform a search.
Larger text, nice look, fewer page loads, a lot more scrolling.
Artist page (live)
Artist page (old design)
Album page (live)
Album page (old design)