Literally, I mean: You may now use the Party Girl's Party Center to fire up the festivities, and the town NPCs may start their own under the right conditions. The update also adds party essentials to the game, like balloons (and balloon animals), party hats, streamers, presents, the Pigronata, and more.
Behind the scenes, beehive-type bees have been nerfed in expert mode, unnecessary player synchronization calls have been “significantly reduced” which should improve performance on servers with high player counts, rain clouds are craftable, town NPCs will try to avoid falling into cliffs when they're away from their home area (the emphasis on “try” in the patch notes suggests their effort will not be met with great success), and the Sort feature will now work on chests. There are quite a number of bug fixes on tap as well.
Developer Re-Logic said in the 1.3.2 changelog that it's already working on the equally-excitingly-named 1.3.3 update. Details and a release date haven't been nailed down just yet, but the studio said it will focus on the Underground Desert.