I used them once when a company refused to honor a rebate that was promised at the time of purchase. I sent in copies of receipts, the forms and the certified mail, sent them documents of the denial letters and then they gave me a case number I think. (It was a long time ago.) Someone contacted the company and gave the company a chance to resolve the dispute or claim against them. The company forked out the rebate. Someone contacted me to ask if the issue had been resolved and I said yes. It was a long time ago, but that is how I remember it.
Yes, I looked it up and dispute resolution is one of many things they do. Here is a website with the details.
http://espanol.newyork.bbb.org/default.aspx?pid=309