Minecraft wiki entry for Overworld_Update, associated text: Various additions to options.
10 new blocks:
Comparators, Dispensers, Droppers, Hoppers, Minecart with chest, Minecart with TNT, Minecart with hopper, Cauldrons, Red sandstone (alongside its variants), and Slime blocks.
3 new items:
Item frames, Maps, and Ender pearls.
Witch huts.
Witches.