Regardless of how identical the setting is, I have to say, I really do like his idea of being able to carve out furniture and such in-place instead of the multi-step process DF has now. It makes sense to be able to do both, actually - being able to move furniture is a definite plus, but how awesome would it be to make a throne out of native gold with natural quartz straddling it seamlessly?
In regards to theft - I'm warily optimistic that he isn't as batshit retarded as Impaler, in that he'll realize that copying every feature, object, plant, and creature from DF is bound to make pretty much everyone hate him (including many non-dfers) in the long run, and that it'll only result in an easily won lawsuit from Toady. And to me, whether or not he can make something that can compete with DF is irrelevant, as DF can't compete with DF - it's always growing, and it's much more than a fortress simulation. To me this looks like a pretest - something that uses some placeholder terminology and features from the game that inspired it in order to test the technology, interface, and appeal of the game. And dwarves certainly aren't copyright Toady One, so the main theme of his game isn't exactly completely stolen.