Minecraft has updated to 1.2 now!http://www.youtube.com/watch?v=QuVn37lb57E
You can read about it here: http://www.minecraftforum.net/index.phpCopy 'n pasted what was posted if you don't want to click the link:The 1.2 Update is finally here! There have been a massive amount of changes since the last big update, and Mojang isn't showing any signs of slowing down. Check out the new feature list!
New jungle biome
Added ocelots
Added cats
Added iron golems
New AI for mobs
Tame wolves can have puppies
Villagers will have children if there is room in their village
New map height limit (256 instead of 128)
New items and blocks
Doors have been updated so that double-doors work better with redstone
Added rare drops for mobs
Many other minor tweaks and fixes
To give you an idea of how high things can be built now, I'll post this picture. The ground level is 4 blocks high from 0 and the little white platform at the top is 256 blocks high.
You're going to be able to build so much larger things now. 
http://i1020.photobucket.com/albums/af328/GoldMammoth/minecraft/65748722.png
that video is epic.
haven't updated yet, having fun with Bacteria mod. Its laggy when replacing all netherrack in nether with glass. i stopped it and it wad 35k blocks in. Imaging if i replaced all nether. I would be laggy and frozen