i thought this could be a thread where people could update on the snapshots every time minecraft release a new one

e.g In minecrafts latest snapshot (13w05a) they have added snow steps which are like a slab but 2 pixels high,
http://i2.ytimg.com/vi/axd513UVgzk/mqdefault.jpg (Unsupported image host)

They also increased the range of the beacons and changed a few thing there.

Also they de-nerfed bonemeal an crops from the last snapshot

If any updates come you van post them here  

Well they're not so much snow steps but varying snow levels. This is to make snow look as though it has depth depending on how much it's snowed and such.

Very interested in seeing a screenshot of what it looks like in a snow biome, with natural variations in the snow.  

In the Minecraft Snapshot 13w06a they had mostly bug fixes

see them here: http://mojang.com/2013/02/minecraft-snapshot-13w06a/