- I'll not be impressed with a cold call just because the callers says that he's a friend of a friend.
- I'll be annoyed when somebody uses my name to make a contact, without me actually recommending the person.
- I'm pretty sure that some people are just using it to harvest the names of companies that outsource to freelancers. That gets annyoying fast.
So, unless, for instance, you sell life insurance or are a recruiter, I think you are on the losing end of the deal.
Worst of all, after a couple of weeks you have to pay just to see peoples' names, so I doubt the business sense of people who use it instead of Orkut. It's particularly silly if you are in the open source business.