Lots of good comments. I would say that if you look at my DS's subsequent achievement test scores, and how things have panned out in terms of needing a grade skip and accelerated classes, that the SB-V my DS took at age 4 was accurate. More accurate were the predictions and comments that the tester made in her report.
If you haven't already, I would recommend checking out Ruf's "5 Levels of Gifted". It has its drawbacks in that it was a small sample size and much of the information was anecdotal, but it was helpful to me to see all the information about what HG kids were doing when they were young.
My belief is that the very early readers who get high scores on early IQ tests has something to do with figuring out the whole decoding thing, which is useful across the board and tends not to go away so much. But this is just my opinion.
And to quote Dottie, the best way to tell where your kid falls on the GT spectrum is many scores over time. You need more data to see a trend. And who knows what it all means in the future. As polarbear (I think) said, try to address your child's particular needs as they come up. They may change quite a bit, and more quickly than you would like, but if you remain flexible, things will be as good as they can be. There is usually no perfect situation for HG kids, but by knowing your own kid and how he/she learns, you will be in a better position to know what type of educational setting will work.
