I don't like Microsoft's solution simply because you need the $15/mo for the XBox Live (I don't care if it goes down when you buy a whole year at a time), on top of the $9-$15 a month you pay Netflix. As for putting a disk into the PS3 or Wii, if you're too lazy to do that its probably better you keep that bit of embarrasing information to yourself.
As for Netflix and Nintendo, this just makes sense. 50-million Wii's sold compared to 30-million PS3/XBoxs. So if Netflix can open up opportunities in a few million more homes, why not? And for everyone complaining about the lack of High-def, do you a) even own a Wii, and b) own any other hi-def device capable of playing netflix? If you don't even have a Wii, or have something else capable of streaming hi-def Netflix to your TV, then this obviously isn't for you, and you need to get on with your life. Even if you only own a Wii and no other computer or console, standard-def Netflix is better than no netflix, right?