A lot of the comments here are related to the idea of whether or not the SAT can be regarded as being much like an IQ test. It can, and psychologists routinely think of the SAT that way. Despite a number of statements to the contrary in the various comments here, taking SAT scores as an informative correlate (proxy) of what psychologists call "general intelligence" is a procedure often found in the professional literature of psychology, with the warrant of studies specifically on that issue. Note that it is standard usage among psychologists to treat "general intelligence" as a term that basically equates with "scoring well on IQ tests and good proxies of IQ tests," which is the point of some of the comments here.

http://www.iapsych.com/iqmr/koening2008.pdf

"Frey and Detterman (2004) showed that the SAT was correlated with measures of general intelligence .82 (.87 when corrected for nonlinearity)"

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3144549/

"Indeed, research suggests that SAT scores load highly on the first principal factor of a factor analysis of cognitive measures; a finding that strongly suggests that the SAT is g loaded (Frey & Detterman, 2004)."

http://www.nytimes.com/roomfordebate/2011/12/04/why-should-s...

"Furthermore, the SAT is largely a measure of general intelligence. Scores on the SAT correlate very highly with scores on standardized tests of intelligence, and like IQ scores, are stable across time and not easily increased through training, coaching or practice."

http://faculty.psy.ohio-state.edu/peters/lab/pubs/publicatio...

"Numeracy’s effects can be examined when controlling for other proxies of general intelligence (e.g., SAT scores; Stanovich & West, 2008)."

As I have heard the issue discussed in the local "journal club" I participate in with professors and graduate students of psychology who focus on human behavioral genetics (including the genetics of IQ), one thing that makes the SAT a very good proxy of general intelligence is that its item content is disclosed (in released previous tests that can be used as practice tests), so that almost the only difference between one test-taker and another in performance on the SAT is generally and consistently getting all of the various items correct, which certainly takes cognitive strengths.

Psychologist Keith R. Stanovich makes the interesting point that there are very strong correlations with IQ scores and SAT scores with some of what everyone regards as "smart" behavior (and which psychologists by convention call "general intelligence") while there are still other kinds of tests that plainly have indisputable right answers that high-IQ people are able to muff. Thus Stanovich distinguishes "intelligence" (essentially, IQ) from "rationality" (making correct decisions that overcome human cognitive biases) as distinct aspects of human cognition. He has a whole book on the subject, What Intelligence Tests Miss, that is quite thought-provoking and informative.

http://www.amazon.com/What-Intelligence-Tests-Miss-Psycholog...

(Disclosure: I enjoy this kind of research discussion partly because I am acquainted with one large group of high-IQ young people

http://cty.jhu.edu/set/

and am interested in how such young people develop over the course of life.)