Will Green effect older homes?

Las Vegas residents, like some many others in other parts of the country, have been seeing their utility rates continue to go up every year. The push to go "green" is also getting stronger as well, which leads me to my question: Will the energy efficiency of  a property becoming more a major selling point (or detriment) in the next two years?

I put a post up asking that on our main blog here. Along with a poll. I'm curious to see the results. - Charles