I agree with Sixen. You should wait before you delete your accounts. Single Player gamers shouldn't be affected. Just don't post on these forums. Unfortunately, Ladder gamers will be safer in solo private games.
I don't know why, but I've got a feeling that RealID won't make it to an active state or, if it does, it won't last long. I'm not going to pretend to know the law, on a federal or local level, but I think Blizzard is crossing the line on this one. It doesn't matter how big and/or powerful a company is, if their policies violate the law (especially on a federal level) they will not be enforceable. And if the proper agencies become aware of such policies, that company will be forced to change them to comply with the law. And RealID, as far as I can tell, violates everything we have ever been taught about protecting your identity on the internet; whether it's your real name, email address or other personal information. Everyone will tell you this, from your online banking sites to your favorite gaming sites.
I will take the necessary precautions to protect my identity, but I'm not going to delete my accounts until I see the results, after the fit hits the shan.
To each his own… I own one of each! ;)
True identities on the internet: "Keep it secret, keep it safe." - Gandalf, Fellowship of the Ring