In case you all were wondering, here's a list of what's been added in the most recent update:
Mobs Salmon: Normal fish that spawns in rivers, and is faster than basic fish.
Spotted Bottom Feeder: A slightly more rare fish that ignores lures, but can be scared to the surface by the player.
Mossyback Bottom Feeder: Rare fish that only spawns in 3 deep swamps. Ignores lures.
Clams: Spawns in the ocean, and hangs out at the bottom. Comes in 4 colors, and can be caught with the net and replaced as a live clam, or killed for clam shells. Ocassionally spawns with a pearl in it's mouth. You must right-click the clam with an empty hand to remove the pearl. Closes when clicked or hurt.
Lobsters: Spawns in the ocean, in brown-red and blue colors. Can be caught to give live lobster item, or killed for claws or tails as a food item. Hurts you when you punch it.
Starfish: Ocean and beach specific. Comes in 8 colors, and moves very slowly.
Fisherman: A new type of villager that will give you awesome items for pearls, or emeralds for fish.
Terrain Features Kelp Forests: Commonly found in almost every chunk of the ocean, grows towers of seaweed and kelp.
Coral Reefs: Discs of different types of coral, combined with a large variety of bushy coral around it. More rare than the kelp forests.
Fisherman Hut: Found in villages, spawns two fishermen inside, who will trade pearls for awesome things.
Items/Blocks Pearls: Can be found rarely in clams. Trade with a fisherman in a village for awesome named fish, goggles or other items. Also create ender pearls by crafting with endstone.
Goggles: Trade with a fisherman to get these, or can be rarely found in the fisherman's hut. Comes with Respiration III enchantment.
Seaweed and Kelp: Found in kelp forests. Seaweed can be used to make sushi, and kelp does not have a use yet, except decoration.
Copious Coral Blocks: Makes for more interesting oceans, at least 15 new blocks for vibrant coral reefs.
New Food: Lobster claws and lobster tails come from lobsters, and can be cooked. Sushi is made with a fish fillet and a seaweed.
Pictures on the OP if you want to see what they look like