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News:
Minecraft is currently in alpha, meaning it's nowhere near finished, but you're free to try it.Keep in mind that it's under heavy development and can be a bit unstable during updates.
You can read more on the development blog, or here.
I'm focusing hard on getting the game to beta, so there will be no more updates to the alpha version of the game until the game reaches beta.
If you're feeling brave, and promise not to complain about the bugs, you can try the latest unstable development version.