InvenSense, the company that makes the MotionPlus accessory, has told Eurogamer the relationship with Nintendo is "not an exclusive" one.
According to bigwig Joe Virginia, other companies are interested in the tech - but he's not naming any names.
"Of course we're incredibly pleased - delighted would probably be a better adjective - that Nintendo approached us... but it's not an exclusive relationship," Virginia told us.
"I can't get into details about other folks that are interested in this technology, but as you might imagine of course there is more interest out there."
The clip-in Wii peripheral adds a "MEMS (micro electrical mechanical systems) rate gyroscope" to the Wiimote. This allows rotation around the X, Y, and Z axes produced by the accelerometer.
When asked if the technology will open doors for Wii developers, Virginia replied, "Oh absolutely. Yeah, absolutely. And the reason we say that is the type of capabilities they have.
"With six degrees of freedom you can basically make any movement at all, and be able to track that in combination with the sensor bar and other sensors included in the Wii remote. Add the gyroscope capability and you have the ability to work in all three dimensions of space," Virginia continued.
"What you're looking at are golf swings; tennis rackets where you can put top-spin on balls; bowling where you can bowl curves; sword motions with forward thrusts; and in Wii Sports Resort the throttle ability." Sounds golden, Virginia.
Motion-sensing cannot work on any more axes; "Six degrees of freedom is the holy grail," apparently. The future will be more responsive and robust gyroscopes that are smaller and cheaper to produce. The power of force feedback within the peripheral is important, too.
"I really think we've just begun to scratch the surface, gaming is a huge application. But if you think of where motions and where motion-sensing can be applied then there are so many applications; this is a great time to be in the business," added Joe Virginia.
"What we hopefully have done is provide our partner with new, increased capability, and what we're so excited to see and await with bated breath is how that will be used.
"Of course in Wii Sports Resort is one application, but what's the future in gaming? I don't know. We provided some great capability and we'll see what happens," he said.
Nintendo is yet to set a standalone price for MotionPlus, but will be bundling the peripheral with Wii Sports Resort - the game used to demonstrate gyroscopic potential during Nintendo's E3 press conference.
We had a chance to see the game and MotionPlus at the show and were very impressed. Head to our hands-on impressions of Wii Sports Resort to find out more.