Also, Ken Jennings is 37, and you can bet he spent 20 years being trained by experts in human learning. So the question I have to ask is, could one train a human child to do this in the same time that Watson has been around? I suspect it's not possible, at least not with consistent results. It looks like Watson is only 5-10 years old, depending on your reckoning.
What's meaningful is comparing energy and time required for creating a human or a computer capable of doing this, as well as maintenance costs.
And assuming Moore's law continues unabated, a Watson-scale machine will be competitive with a human within five to ten years. Given that it's already functional, I would bet money that it will be cost-effective compared to Ken Jennings by 2045, whether through advances in computing or energy. I wouldn't bet it will be sentient, but just that we can build one and set it up to answer questions cheaper than we can raise someone with as good a head for trivia as Ken.
I would certainly hope that we can do better than nature in this regard.
Oh, and while we can't synthesize ribosomes yet, we can in fact custom-design DNA and inject it into an existing cell: see http://en.wikipedia.org/wiki/Mycoplasma_laboratorium