As sizzle says the link is dead, so i can't offer more insight, although there have been a few simillar posts this past week, I've provided details on my blog.
These types of scams are credit card scams, and the pictures usually stolen. If you have to do more than give a name and phone number or address for an outcall then don't bother. Anyone requiring more information is hardly going to provide said services and is far from discreet. If you have to jump through hoops then you are just part of a circus act and will likely see charges on your credit card or phone bill that you have not authorized.
From the sounds of what slurp says, you have to visit a site and the number is displayed already. Usually they want' you to enter your credit card info.
This scam sounds like it's the back door to a toll number, by you calling it your automatically accepting the charges that can be as low at 3.99 a minute or 50 bucks for a one time shot. This is a familiar scam in some states and Europe. Be careful boys while we have many great sp's and visitng providers there's just as many scamers and thieves out there to do you wrong.