New weekly snapshot is up at
Mojang.com Some interesting additions coming!!
12w34a
Added item frames
Added cobblestone walls (yes, mossy too)
Maps now align to a grid, making it easier to create adjacent maps. Maps can also be cloned
Stairs now auto-arrange into corners. This is a test and may change based on feedback
Mobs can travel through portals
Leather clothes can be dyed
Removed the wip block from the creative menu
Added two new crops and associated items
F3+P will toggle the auto-pause when the window loses focus (its for debugging, mainly)
F3+H will toggle detailed item descriptions (also for debugging)
Added arrow-sensitive wooden buttons
Trapdoors can be placed in top-most position (based on cross-hair aim)