After writing the GRE last year and looking at admittances this year, I am wondering what the value of the GRE is. While I did well on it, I don't think the questions really prove anything. Consider that the first section on math is high school level, the second section on verbal is primarily enhanced by vocabulary and the third section is apparently subjective.
Nobody really needs this stuff. If you are in a program that uses math, you're going to have to have much more math than the GRE to have gotten by. If you are in a program that requires lots of words... well it might indicate how well read you are but wouldn't reading comprehension and writing samples give a better example anyways?
Honestly I don't understand why the standardized test isn't the LSAT. The LSAT primarily tests logical reasoning and analytical abilities - skills required for every field. Personally, if i were a professor, I would give much more weight to an LSAT score if my applicants had that than the GRE.