I've played with a Wiimote for simple pointing on my laptop. I think they make a great, affordable alternative to a Gyromouse for presenting, but the process to connect with Bluetooth every time you turn on was a little daunting.
I think it's a great way to do presentations with SW, but I agree with Ocell, it can't compete with a dedicated 3D control device - except on price. $600 for a navigator vs. $40 for a Wiimote and $30(?) for a bluetooth dongle [if it's not build into your PC, which at this point it might well be] - somebody just starting to get frustrated with a mouse might take the baby steps first.
