[Update: The game is now available via Steam - click here to grab a copy.]

Well this came out of the blue, huh? Terraria first appeared in the limelight less than a month ago, and is already getting a release today on Steam. To celebrate the impended and inevitable boom in day one sales, the Terraria team has released the above trailer.

In a forum post over on at Terraria Online, developer Jeremy 'Blue' Guerrette explained that the first release will have some Steam integration - namely Steam chat and a built-in account system - but that there are no achievements for now. In fact, there's a whole list of features that will be missing for the first release, but considering that it's pretty much Minecraft 2D, it's not surprising that the team are using the same development model.

Still no word on when it will appear on Steam today, but it shall set you back $10. Check out the official site for everything you need to know.