Minecraft has become more complex, as in redstone, emerald, and big stuctures!

Newly added: Tripwires, Jungle and Desert Temples, New ore (Emerald), Villager Trading, Faster Boats, Better Pressure plates, And much more!

What will be here in the MC 1.3 Update: Tripwires, Emerald, Villager Trading, Faster Boats.

I am not sure If Mojang will add Temples, but as I think they are a great idea!

Bug Fixes: Arrows now do not inch their way to the top of a block, Slab placing is much better, and now you can fire arrows at pressure plates.

Minecraft Recently added a PLUBLISH command, wich allows other players to go on your own single player map! This will be released in MC 1.3, as it will help many players if they don't know how to set up a server.

Also, In MC 1.3, there will be a new game mode: Adventure Mode. This allows players unable to break blocks.

This is a great expansion for map makers, if you are not allowed to break blocks.

Good Luck with your Minecraft, and have a happy day!