This update is mostly patching bugs and reworking some aspects of the new sandboxing system - almost all of it is backend and you will only really notice a more consistent and bug-free experience. However, 10 new blocks and walls have been added and made craftable in the form of ore blocks, glowsap blocks, and a few other decorative items like glass and latticework blocks.
Weapons now have a new system in place that allows players to 'charge up' the attacks of certain weapons for effects like stronger projectiles, dash attacks, or longer range.
Additionally, two new early-game events have been added to help keep you busy. Look out for rainbows after it rains, and watch every morning for invasive weeds that could disrupt your planet's balance :)