The powerups include Flock of Birds, Space Egg and Pig Puffer, which cause varying degrees of destruction. The new levels have obviously caused new water physics to be added to the game, which should switch things up a bit.
From the update description:
Make a splash in 30 NEW LEVELS!
Get ready for the ultimate underwater boss level!
Three-star levels for 3 new bonus levels!
Use Flock of Birds for a pack of destruction!
Create black holes with Space Egg!
Expand the pigs with Pig Puffer!
Check back daily for a free power-up!
Power-up specific leaderboards in addition to regular leaderboards!