Minecraft wiki entry for Best_biomes_for_homes, associated text: Massive amounts of wood.
Jungle temples have loot and redstone in them and can also serve as houses. Be careful of the dispensers that shoot arrows.
Ocelots spawn naturally. They scare away creepers, which may be hard to notice due to their green texture against the green leaves.
Grass blocks here are vibrant green.
Melons and cocoa beans generate here.
The large jungle trees can be made into treehouses, which are easy to protect. This makes it a great biome for multiplayer bases.
Parrots spawn naturally. They mimic the noises of nearby mobs, making them useful for detecting hostile mobs.
Bamboo naturally generates here, great for crafting scaffolding and sticks.
Pandas can be found here.
Zombie villagers spawn here wearing unique clothes which can be cured into jungle villagers.