Nintendo president Satoru Iwata has said that he anticipated the announcement of competing motion controllers in 2008.
"To tell the truth, I expected them to come up with stuff like this last year. So in my mind they're later than expected," he told The Times. "I'd like to say to them, 'Welcome to the motion-control world!'
However, he pointed out, there are no details on software support, pricing or availability from Sony or Microsoft, both of whom demonstrated competing technologies at E3 last week.
"So, I am not in a position to judge whether they are a threat or not. And they should bear in mind that over the next year Nintendo will not be standing still.
"We're always at work on something new. I am actually looking forward to engaging in that sort of competition, because it gives our whole industry the chance to expand the gaming population."
Iwata's pet project at the moment, he said, is the Wii Vitality Sensor, which surprised the audience at Nintendo's conference.
According to Iwata, it also surprised his own employees, because he hadn't told them about it and had even edited the conference video himself on the plane to Los Angeles from Japan.
"This is what I find interesting," he said of the device, which measures bloodflow to gauge relaxation levels. "The idea of making something that is invisible, visible is fascinating."