Hardcore Mode
I Mentioned it briefly in a tweet, to let everyone know it was on its way. I can verify now that It will be in 1.0.5 and it will offer to those who find themselves wanting more to do in Terraria, an option at just that. Yes, it will be an 'option' and wont be forced on everyone.
Here are a few things I can say about it.
Its a Character Based option, so your HCM character can move between servers. Be careful though. As a non-HCM players grief can end your run quite easily
Its set at character creation and can not be toggled off for that character afterward.
If you Die, thats it, game over. You must start a new Character at that point. Your world however will not be effected by this. So this means you may start a new HC mode character and utilize the house/chests your last character left behind. You will also see a gravestone where your old character met his fate.
It really changes the way you play the game, as every action could be your last. Caution is a good thing. Also, There is more of a sense of accomplishment as you play.