I invited several friends to my linkedin account. I will invite more later, because it is an easy way to find old friends to keep in touch.
But it is hard to delete a person from my connection list: I did not find any button to break a connection. (This sounds like I hate somebody, no, I only do not want to keep many names that I can not remember well.)
Finally, I got this link somewhere:
Hopefully, when I delete a person from my connections, he/she would not receive an email like "Jun hates you! He does not want to see you any more!" :)