This clearly looks like an Internet Deception to me.

A recent topic on LinkedIn in which I became engaged and with which I have strong feelings goes like this, "...when others import their address book into sites such as Visisble Path, Jobster and others and my name (or anyone’s) is in their addy book it appears we are members to those who search for out name. I feel this is deceptive and promotes unwelcome invitations from unsuspecting people. It is not the fault of the members; it is the site that has it set up this way. I am talking to a lady from Visible Path tomorrow regarding this situation but I am curious if others feel this is a deceptive act on the part of these sites. In an email she admitted I am not a member, but it appears that I am due to my name being in someone else’s address book. Essentially, they are using the members address books to deceptively increase membership. "

My response went like this:
This is clearly deceptive. I may or may not be correct in saying that the company that does this can quite possibly be accused of taking a LIBELOUS ACTIONS when they post your name (and mine?) for all to see and use. The paragraph below is taken from Marks, P. (2006): Pentagon sets its sights on social networking websites, in: NewSienctistTech, 06/09/2006. This is also referenced in the web resources below. This is all kind of scary when combined with the abusive and deceiptful efforts of companies like the one you mention in your initial question. "Advanced Research Development Activity is a role to spend NSA money on research that can "solve some of the most critical problems facing the US intelligence community". Chief among ARDA's aims is to make sense of the massive amounts of data the NSA collects - some of its sources grow by around 4 million gigabytes a month.The ever-growing online social networks are part of the flood of internet information that could be mined: some of the top sites like MySpace now have more than 80 million members." Other web references below provide interesting viewpoints on this provocative question.

Links:
http://www.shrm.org/hrmagazine/articles/0405/0405berkshire.asp
http://www.newscientisttech.com/article.ns?id=mg19025556.200&feedId=online-...
http://www.socialnetworks.org/