That's understood which is why I'm not on it.
I don't trust the rest of the people that are on there to control their views of who their friends/contacts are, conversations etc.
it's bad enough when some idiot includes my email address on the TO: or CC: line in an email that includes people I don't know.
I normally start spamming the crap out of that list to make my point.
I use the non Facebook/twitter technology the way I want to and can control it to the level I want to. People who I want to have my other information have it. If I have not spoken to you in ages and you don't have my contact information, there is a reason for that.
From a business point of view, it's debatable on whether or not it helps make the company money. It is good for updates, if people connect to you. From that aspect, it's more targeted than a website.
Still hate it
