The Wii Scene is fastly becoming one of the Great homebrew scenes, any scene that doesnt require you to invalidate your warrenty by installing a modchip is great in anyones books. One worry is that there is a possibility however small that the homebrew channel can brick your Wii but like everything follow everything to the letter and you should be ok.
As for the Wii Scene we have seen many emulators released for all these systems so far :
MAME
Midway Space Invaders
Atari ST
Gameboy Colour
Game Gear
GBA
Nes
PC Engine
ScummVM
Genesis
Sega Master System
Snes
Thats already a fantastic amount of emulators, if the Wii Specs are to be believed then we should in theory see emulators as fast as what appeared on the Xbox but what do you think is the best we can hope for ?, is full speed N64 doable, let us know via comments, also for purists do you prefer emulators played with a normal controller or the Wiimote, again answers via comments.