You can still use your mouse.

There are a couple of really good things with the mouse that are hard to overcome with any form of motion technology as long as our computers have the interfaces they do today (as in Windows, mainly). It's easy to be completely still, for one. Incredibly high precision, for another. It's small and portable, robust and all you need is a small flat space to sit it on. There is very little chance of fake input (someone had a good phrase for this in a thread a couple of months back, but I cannot remember it..).

If you can beat that, coupled with the other three areas I mentioned, then sure, it can replace the mouse. But in the forseeable future, that won't happen. I don't think any kind of camera could point with higher precision and more ease than a mouse.

But really, how often do you see people using a mouse in science fiction?

The mouse is close to perfect as is. Natal would be a step back in terms of sensitivity and reliability i think.

Maybe it could be like the multi-touch. The problem is there's no tactile feedback to it, you always need a reference point of some kind, to indicate when you want to actually interact with it. With multi-touch the actual touching acts as the reference point for that.

You know, as corny as this may sound I think the mouse's sucessor will probably come from Apple, before Microsoft. Apple is a company that has the user experience at the helm, they look at the interface in ways that can enhance the user experience, Microsoft is not at all like that.

Even from a distance I can already tell a bunch of practical things that don't quite work with something like Natal as a sequel to the mouse. I'll wait for other companies to show their solutions, I wouldn't doubt Apple has something in the pipeline. They already patented an IR pointer remote controller interface, which frankly probably works much better once you get it in the consumer's hands, than something like Natal.

I can see it becoming an adjunct to the mouse but not replacing it.

No, I already posted a simple tech sample about the limitations of Natal. Let' just say that Natal is based around broad motions and at this time there is no sample of precision input for pointers. It's likely possible, but it will be just as weak as the Wiiremote 1:1.

Maybe something that goes around the index finger similar to the glove in "Minority Report" for tracking specific movements would work.

I think there will be strong uses for it in use for Windows eventually.

I don't see it replacing the Wii Remote.

Perhaps it could be nice for certain things, but generally I don't think it can replace a mouse.

Now excuse me while I go hug my Logitech G5.