Ken Jennings describes what it's like to play against a machine - Slate Magazine

"Watching you on Jeopardy! is what inspired the whole project," one IBM engineer told me, consolingly. "And we looked at your games over and over, your style of play. There's a lot of you in Watson." I understood then why the engineers wanted to beat me so badly: To them, I wasn't the good guy, playing for the human race. That was Watson's role, as a symbol and product of human innovation and ingenuity. So my defeat at the hands of a machine has a happy ending, after all. At least until the whole system becomes sentient and figures out the nuclear launch codes. But I figure that's years away.

Nice article about what it was like to play against Watson.