My wife and I were considering installing solar panels on our roof recently but decided against it due to some recent developments in nanotube technology.
Referenced
here and
here There's currently some very promising developments in the advancement of solar technology using a nanotube-derived technology called solar concentration coming out of MIT. Basically it uses refractive materials in windows to collect the solar energy in cells around the edge, and each cell will return approximately 40% more energy than the average solar cell of today.
Since my house is east-west oriented, we get full sunlight in the back in the morning, and full sunlight in the front in the afternoon, so I could see this being an ideal solution for someone in my position. And that's why we decided to hold off on Solar Panels until this is made available to the public, at which time we'll do cost comparisons and make a decision.