A recent interview with a Lionsgate representative hinted that Nintendo may be getting ready for a online movie store for the Wii.
"I think when we see the Wii come into the market with the ability to stream movies, which I think is maybe going to happen as soon as this year..."
If you stop and think about what target audience the Wii was designed for (kids, non-gamers,older generation, etc), its less likely they will be in to downloading movies or otherwise accessing video from the Web.