I'd say no. The cost of the silicon wafers in terms of $ and energy to produce has remained about the same. Refinements in process that make it a little cheaper have been offset by higher energy costs. What Moore's law has done is make it possible to fit more and more transistors in the same space, not make the space cheaper.
I'm calling bull on this one. Photo-voltaic solar is still ruinously expensive and it will require more than incremental innovation to change this.
A lot of debate in the comments on this article: http://www.pbs.org/cringely/pulpit/2008/pulpit_20081030_0055...