Another game has flown into my radar. It's called Minetest (http://c55.me/minetest/).

Pros:
Free alternative to Minecraft
What Minecraft probably looked like in "the old days"
REAL fast download and real fast loading

Cons:
It's not a Minecraft replacement
This is a game in development and is probably still missing things similar to Minecraft
...but if you like in-development alpha/etc stuff, this could be a pro to you

Decide for yourself! All I know is that I'm playing it