I don't understand these meme of degrading IQ as having little real world value.Haven't you read Lewis Terman, author of the Stanford-Binet IQ test, on the subject?
"There are, however, certain characteristics of age scores with which the reader should be familiar. For one thing, it is necessary to bear in mind that the true mental age as we have used it refers to the mental age on a particular intelligence test. A subject's mental age in this sense may not coincide with the age score he would make in tests of musical ability, mechanical ability, social adjustment, etc. A subject has, strictly speaking, a number of mental ages; we are here concerned only with that which depends on the abilities tested by the new Stanford-Binet scales." (Terman & Merrill 1937, p. 25)
Or perhaps you would prefer the point of view of David Feldman, a psychologist specializing in the scholarly study of precocious and highest-IQ individuals?
"Put into the context of the psychometric movement as a whole, it is clear that positive extreme of the IQ distribution is not as different from other IQ levels as might have been expected. . . . While 180 IQ suggests the ability to do academic work with relative ease, it does not signify a qualitatively different organization of mind. It also does not suggest the presence of ‘genius’ in its common-sense meaning, i.e. transcendent achievement in some field. For these kinds of phenomena, IQ seems at best a crude predictor. For anything more, we will have to look to traditions other than the psychometric and to variables other than IQ." (Feldman 1984)
The one independent science writer who has had access to Terman's longitudinal study files at Stanford points out that IQ tests are a great way to miss future Nobel Prize winners. Amazingly, Terman’s study catchment area in California included two future Nobel Prize winners, but both were rejected from inclusion in the study because their childhood IQ scores were too low (Shurkin 1992, pp. 35, 395).
REFERENCES
Feldman, David (1984). A Follow-up of Subjects Scoring above 180 IQ in Terman's Genetic Studies of Genius. Exceptional Children, 50, 6, 518-523.
Shurkin, Joel N. (1992). Terman's Kids: The Groundbreaking Study of How the Gifted Grow Up. Boston: Little, Brown.
Terman, Lewis & Merrill, Maude (1937). Measuring Intelligence: A Guide to the Administration of the New Revised Stanford-Binet Tests of Intelligence. Boston: Houghton Mifflin.
After edit: I see several replies elsewhere in this thread are citing Wikipedia articles as the last word on their subjects. It's important to point out that most Wikipedia articles don't reflect the best research literature known even to Wikipedia editors,
http://en.wikipedia.org/wiki/User:WeijiBaikeBianji/Intellige...
largely because the Wikipedia articles on human intelligence as a broad subject have been the subject of much edit-warring for years
http://en.wikipedia.org/wiki/Wikipedia:Arbitration/Requests/...
and some editors continue to push their point of view, relying on unreliable sources, into multiple Wikipedia articles.
http://en.wikipedia.org/wiki/Wikipedia:Arbitration/Requests/...