CamWorld notes (on 02/16) that Network Solutions sells its domain database to marketing firms. This is loathsome but not particularly surprising; their whois tool has provided email and snail addresses for every domain owner in their database, for years.
Don’t get me wrong — this is worse. NSI is serving up custom views of its database, data in bulk to exactly the sort of people who know how to abuse it (junk mailers).
IMO this requires two immediate responses. The first is to contact your senators and representatives to request an investigation. As pointed out by the Electronic Privacy Information Center, this sale may not even be legal. Copy the text at that last link and send your own letter to Washington DC; find the addresses of your senators and representatives here.
The second is to transfer all domains away from NSI immediately. The added benefit is that you can save $20+ dollars per domain per year by doing this. I’ve had good results with these registrars: Joker, Dotster. Dotster makes the transfer process easy; they do not require domain holders to fax in documentation — some registrars do.
To be clear, NSI may well be selling domain registration information for domains registered through other approved registrars. If they are, then transferring your domain away from NSI won’t stop your privacy from being violated, but still I think you’ll feel better if you’re not paying NSI to violate your privacy. I know I will.