Every 2-3 years I do the math on solar cells for my home. I live in a house with a large flat roof and in one of the top 10 cities in the world for solar potential, so it seems to make sense in theory. Unfortunately, even with large government / power company subsidies, the math never works as an investment.
The problem for me is not efficiency - I have enough flat space on my roof for a lot of cells - but cost. We need a solar technology that can be rolled out of the factory like carpet from Dalton, Georgia. To this end, this looks promising.