World Solar Insolation vs. Solar Installation

This is an interesting chart that showed up in the IEEE Spectrum magazine, October 2007. Green areas show where solar power is installed, and yellow areas show regions with the most sunlight. It shows how the politics can influence technical decisions. Germany, New York, and Japan have many installations of solar power, but relatively little sunlight. It's interesting to note that China seems to be a prime spot for solar installation, but doesn't use a significant amount. Is this a possible part of the solution to China's smog problem?

The other interesting fact, pointed out by a friend of mine who is a solar power buff, is that the whole world has installed 3705 MW of solar power (as of 2005), which is about the same amount of power a single new nuclear power plant with twin reactors could generate. (I wasn't able to verify this, if someone can, please post a comment).