Solar Thermal may be dead: http: //www.greenbuildingadvisor.com/blogs/dept/musings/solar-thermal-dead
But PV will reach grid parity soon: http://climatecrocks.com/2012/05/30/solar-grid-parity-inevitable-wholl-be-the-leader-in-this-disruptive-technology/
Even though right now it's in the midst of a "correction": http://www.greenworldinvestor.com/2012/05/31/6-reasons-why-the-time-for-buying-solar-stocks-has-arrived/
Cheap gas is delaying renewable uptake, but using gas for making electricity inherently has a VERY low overall system efficiency, and seems a waste of a non-renewable energy source.
Conclusion: Inevitable but rocky growth for PV, with a Darwinian edge.
By the way, Jay Burch et. al. at NREL are trying to save solar thermal by finding a technology that provides a "disruptive cost reduction". Here's an abstract of a forthcoming report:
The objectives of this report are to:
(1) Identify the target market for solar hot water heaters that will provide the largest U.S. energy savings potential relative to other advanced hot water heating technologies, and, (2) Identify potential technology pathways and cost/performance targets that must be met to enable solar hot water heating systems to achieve large energy savings. The market environment for solar water heating technology has changed substantially with the successful introduction of heat pump water heaters (HPWHs). The addition of this energy-efficient technology to the market increases direct competition with solar water heaters (SWHs) for available energy savings. It is therefore essential to understand which segment of the market is best suited for HPWHs and focus the development of innovative, low-cost SWHs in the market segment where the largest opportunities exist."