The patch is huge and has a lot of content in it. From now on, there is a new creature system. It allows players to place all sorts of creatures. The patch reworks the way resources spawn and completely removes plant harvesting. Also, the character creation screen received a major overhaul.
The changes don't stop there, as many changes were applied to the World and Build Sites, formerly known as Claims. Lastly, There were some changes made to the Inventory, Combat System, and Achievements. Of course, I can specify all changes made, so if you are interested in the detailed patch overview, it is best if you head to the official forums.
You can read the full patch notes here.