I typically type ~90 wpm, and using Dvorak I was up to ~110.

That's great and all, however I am very seldom typing words. More often, I'm inputting key-bindings and pressing shortcut combinations. Some programs offer Dvorak-based keybindings, but not all, and unlearning all those keybindings on top of the typing instincts provides yet another layer of frustration. Not to mention the fact that every time I used my wife's computer I was effectively crippled ;)

Overall, I would say learn Dvorak if you just are really curious or do a lot of very serious word-based typing. Otherwise, it's just a waste of time.