My understanding is that the 2400 point SAT is the old 1600 one with a 100% meaningless writing section tacked onto the end. I remember something about that being ignored by universities and such because "the scoring isn't properly calibrated yet" or something along those lines.
It's still used in case of an anomalously low score. More people than you would think try to get into college with absolutely NO writing ability, and then crash and burn hardcore. Speaking as a grader for a few intro engineering classes (okay, programming really), people who can't write to save their lives really shouldn't be in college until they improve...they drop out really, really fast.
I'd say that the writing section is the best indicator of actual ability, or at least it's the hardest thing to get inappropriately high scores on. Anyone with very narrow training can do very good on math, and plenty of people can do very good on the reading kinda stuff without much true comprehension. The writing part weeds out the people that -need- weeding out.
Yes, but then the question is "How smart do you have to be to recognize their scheme?"
Of Cause!
The test isn't the test itself, but is in realizing that the test is a sham!
I've seen one that ACTUALLY DID THAT. You entered your email address at the beginning...and it sent you your results ten minutes after you stopped submitting pages, where your score was solely based on how early you stopped playing. I got up to somewhere around 34 pages, even after I realized that the questions seemed to be repetitive and randomly generated >.> I wonder what that says about me, but let's just say my results weren't triple-digit.
Another awesome one I saw...it logs the IP address you took the test from, and it gives you a special image URL to post your results, with a picture of a rabbit with one of those fancy graduation caps on his head along with the number you got (which I think was a minimum of 120+). But it only shows that picture to your IP address. Everyone else loads a different picture, rabbit in a dunce cap, score around 89...which meant that for a couple days, Livejournal was full of people with sub-100 IQs and posts saying "Wow, I didn't expect to do this well, I'm really surprised!"