I have huge issues with the levels...but I agree with Kriston that they can be useful. In particular, they were helpful in making DH see that DD is gifted, and likely HG+.
We did participate in the beta test. Honestly, I think that even if one believes in the levels one can probably get a better idea of where one's child fits in by reading the book. The online system, by it's very nature, focuses on a very few developmental skills, which, as we all know, are not the whole picture of a child. But, if you want to convince a reluctant spouse, and you don't want to read the book, that could be worth $45.
We did have results that were in line with what we expected (though, to our amusement, we did it twice with oddly different distributions).
I also think that there is a risk that anyone familiar with the levels will "remember" milestones that will place the child at the LOG that the parent believes the child belongs at. It's just the nature of memories of things that happened years ago that, unless you've got them written down, it is so easy to convince yourself that they happened at a slightly different time than when they really happened. And it is also easy to interpret many of Ruf's milestones differently. I imagine that a person who wants a child to be gifted will apply a much more liberal definition to "plays with a shape sorter" than someone who is hoping the child is not gifted, for example.
Okay, I've babbled long enough.
