Hey guys! Today I'm gonna be showing you the new mojang snapshot: 12w49a! The awesome kickstarter to 1.5 includes:
Fireworks!
Enchanted Books!
Transparent blocks on dispensers, furnaces and crafting tables!

So, lets start with the smaller updates
NETHERBRICK SLABS
Crafted like any other slabs, these slabs are perfect for your nether dungeons, and add that same feeling to netherbrick as you have with cobblestone, sandstone and stone bricks!

TRANSPARENT BLOCK CHANGES
Transparent blocks, such as torches, slabs, rails and repeaters can now be placed on crafting tables, dispensers and furnaces by holding shift and placing them. (its not just transparent blocks, normal ones as well. transparent ones just stand out more)

ENCHANTED BOOKS
Enchanting a book works. It will give you one random enchantment which can be applied to anything using the anvil. It is like a way to carry enchantments.

FIREWORKS
Fireworks are the biggest update. Though they are just for decoration, they look really cool. To craft your firework, you will need a fire work star. This is crafted by putting different dyes in the crafting table with 1 gunpowder and there are different features you can add to the crafting table as well as your dyes. You can add one feature from each category. There are effects and shapes. The shapes are firecharge to make it a large ball, gold nuggets make it a star-shaped firework, a feather will make a burst one, heads will make it a creeper shaped one. The effects are glowstone dust which makes a twinkle and the diamond will make a trail. Now you have your firework star. If you add more dyes it will fade to those colors. Now add that to paper and gunpowder and you get your firework. You can add more gunpowder to the fire work to make it's flight duration longer. Right click the ground to fire but they can also be fired in dispensers. That's it for this snapshot, bye :)