An article in New Scientist discusses some of the shortcomings of the IQ tests.

Having a high IQ does not mean you are smart. It just means you have certain mental tools. However, lots of high IQ people do not actually make very good use of those tools.

Just as an example, the article mentions that Mensa Canada was surveyed, and its members showed the following beliefs.
44% in astrology
51% in biorhythms
56% in aliens

Clearly, their high IQ did not protect them from absurd beliefs.

New Scientist discusses the need for an RQ test, measuring the ability to make rational decisions, as opposed to IQ. People of high RQ would make much better leaders, both in politics and in business. An RQ test would prove highly useful in selecting such people. Such an RQ test would have eliminated Bush junior as American president, for example, and kept the USA out of Iraq.

Any other views on IQ and rationality?