Just be happy you don't have any burning sensations when you Wii
I have a new game involving the Wii! When it gets really hot you can unplug it and toss it round with friends. 'Hot Wii' (Plays like Hot Potato)
I can imagine they will have an upgrade for this in the future. The fan is so quiet I've never heard it... but then I've never really paid much attention to it either.