Well since AH just rendered your argument moot, I'll shift gears and talk about placing personal info on these networking sites.
I think that only a handful of people here know my government name via Facebook and they are people who I sincerely trust.
Plus, there are numerous privacy options available on Facebook. It's just a matter of taking precautions and using your common sense.
I'm not on MySpace, but I'm sure there are privacy options available on their website.
If you feel your privacy is being compromised, you can always opt out of using Facebook or MySpace.