Yea, I've noticed that about the board. Even I rarely check it. I'm not the healthiest person these days, otherwise I'd have been attending the actual PSAO meetings this past school year.
Ball Jointed Doll, is just that. A doll that has ball joints. They became well known via Volks, and they're very customizable, the one I have is almost two feet tall, and they're not cheap. You can choose their eyes, their wig, even have a customized paint job done to their faces to give them their own personality. To best get an idea of the asthetics, check out the site
http://eluts.com and look at the delf dolls, or the delf artist dolls.
Doing a google search for SOOM, dollshe, and bobobie will help to show some of the various looks. There's also wishels, Doll in Mind, Dream of Doll, Obitsu, DollZone, Volks, and a bunch of other companies I can't remember. My girl is a Boy&Girl company (which is impossible to find via google) mold, and I made her wig and did her face up (the term used to describe the painting on the face that gives them there eyebrows, lashes, and definition in the lips)
Does that help? As being within the hobby, it's kinda hard for me, looking out, to determin what those who aren't in the hobby need to know. But actually, the funimation updates when they were at Otakon this past year are dealing with BJDs. There's even a shot of my girl there (she's got white hair, and a blue vest. Terrible shot of her, she looks a fright)
BJDs anyone?, Ball-Jointed-Dolls
Also, if you want to ask the psao guys, it'd be better to get in touch with them personally, as the board is just about dead, with the exception of three or four people. 
