Are all your users right-handed? Or is it just you?

I was reading an article on the BBC's website (again), about the new controller for Nintendo's forthcoming Wii console. It's being demoed at the E3 games expo in Los Angeles, and it seems like a real breakthrough in interaction.

There are two controllers: one for each hand. One of the controllers is long and thin, one round and curvy. The examples of the games on show at the Expo include a tennis game, a golf game, and a couple of shooting games. It sounds great for tennis: there's an avatar on the screen, and you swing your long thin controller as if it's a tennis racquet and your avatar hits the ball. This is so much more like playing tennis than playing with a normal controller - great innovative stuff.

The shooting game is apparently a bit more difficult to get used to, as you shoot with the long thing controller and use the curvy one to move around. The interesting thing though, is that throughout the article it's described that you hold the long thing controller in your right hand and the curvy one in your left hand. So you play tennis with your right hand, and you shoot your gun with your right hand.

The question is: can you switch hands? The Wikipedia article doesn't mention explicitly which hand you should use, but all the pictures show the long thin controller held in the right hand. This blog suggests right-handers only.

I hope you can use this controller in both hands: it's a really exciting development. I don't see why you wouldn't be able to switch hands, but if you can't then 10% of the population are going to be pretty disappointed (and 50% of chimpanzees). As a left-hander, I have my fingers crossed....

And the lesson to be learnt? Same old lesson: know your users. Think about who they are, what their characteristics are, and what they want to do.