I think Watson would make a better primary diagnostic tool than most doctors, but there is an interesting question about decisions. There are so many variables involved in medicine that having something that can actually synthesize all of them seems like it would be a net positive, but I'm not sure what it would take for me to feel comfortable about the machine making a decision on my treatment. I can't imagine the time won't come (during my life) where diagnostics and treatment can be done by machine.