• Each shelf can choose its own cover captions: long-press a shelf, then Shelf style > Cover captions. For example, series names on your Series shelf and titles everywhere else. Shelves you leave alone follow Settings > Cover display.
• A shelf inside a shelf of shelves can now have its own theme. Until you choose one it wears its shelf of shelves' theme, shown as "Same as …" in Shelf style and the Theme menu, and the Theme menu's This shelf row now sets the shelf you're on.
• The line under each cover is now called a cover caption: Settings > Cover display > Cover captions, and Settings > Text size > Cover captions.
• Show text below groups is now a single switch, Show author below series. The Custom option for groups is gone: the only thing it could add was a series' author. If you had Author or Custom chosen, the switch is on.