So, there have been some developer previews released recently and I figured I'd give everyone a little heads up about what is likely going to be coming in the next update for anyone not paying attention, because there are some pretty major new things:
New Biome: There is now a Jungle biome.
New Tree Type: There are not "Jungle Trees". The trunks are a yellowish brown color. And they can grow extremely tall. The really tall ones grow with a 2x2 trunk, and you can plant 4 saplings in a 2x2 pattern and use bonemeal on them to grow a super tall 2x2 tree. Jungle trees will also grow with vines on the trunk and hanging from the leaves.
Vines: While vines were in the game already, now any vine that is on a wall or solid surface can be climbed like a ladder.
Cats: Wild cats have been added to the game, currently they only spawn in Jungles. They can be tamed similar to wolves. Wild cats have an orange patterned coat, like a ocelot, but change to a more traditional domesticated cat pattern when tamed. They will follow you like a tamed wolf, but won't really attack anything other than chickens. They can be told to sit like wolves as well.
Wolf/Cat Breeding: Tamed wolves can now be breed to give tamed wolf puppies. You use fresh uncooked pork instead of wheat to make them breed. Currently it isn't known how this affects feeding them to regain their health. It might make it impossible for them to regain health. Cats can also be breed, using fresh fish.
Fire Charge: A new crafting recipe has been added to create the Fire Charge. Which can be used in dispensers to make them shoot a fireball.
Bottle o' Enchanting: Some kind of new potion, recipe currently unknown, that when thrown will give out experience orbs that the player can collect.
New Mob AI:
Zombies: Zombies are now much smarter. They can negotiate obstacles and even find their way out of small mazes to get to the player they are chasing. So no more hiding around corners to escape zombies. Also, on hard/hardcore mode only, zombies will break down wooden doors!
Skeletons: Skeletons will now seek out shade when the sun comes up to stop themselves from burning in the daylight.
I think that is it for now, but there will probably be more developer builds released with some other additions before the next update.