Just to let you know, the whole Dvorak think is pretty much bunk. There was one, singular study that showed that Dvorak was a faster setup for typing, and I will give you 3 guesses who ran it. Would it be too small of a hint to say that the guys name began with DV, what with the huge number of names like that? Anyways, all the rest of the studies show no appreciable difference between typing setups, and the whole, "Qwerty was designed to slow down typists useing a typewriter" thing is an urban legend. I'm saying this from memory, but there's an article about it here
http://www.utdallas.edu/~liebowit/keys1.html
So I wouldn't swap out your Qwerty keyboard just yet.