Found out about this game a little while ago ( couple days), and it seems kind of interesting. Seems to be in the same vain as Minecraft in the building and crafting sense, but with more of an action orientation. Also looks like while they inintaly were looking to release it in June, the announced today they are going to Hit Steam on the 16th for $9.99.
If you do a search on youtube they did some lets play videos to show off the game:
Lets play with Devolper and a tester
Terraria