Well, I guess I'm committed to Dvorak now. Prompted by some tips from Ryan Poling, I just rearranged the key caps on my Powerbook's keyboard. In the office, I use an external USB keyboard that has already been fixed to support the Dvorak layout. But, this afternoon on the bus ride home, I cracked the 'book open to hack on my Rails bookmark manager - and realized that although the key caps were still QWERTY, I was starting to think in Dvorak. Light at the end of the rainbow...
Ryan suggests buying a little wire tool for popping the key caps off. I just followed the tip of very carefully pushing down on the bottom edge of the key while gently pulling straight up on the top edge. Worked like a charm.
It also strikes me that Dvorak should be a touch more efficient for writing code, with the curly brackets and punctuations positioned a bit more optimally. If I pay attention while typing, I'm really surprised at just how little finger movement is required.