There truly is a difference between "social networking" casually and religiously. What I mean by that is when you get too attached to your life over the Internet, it becomes your life. Disregarding all other things you care for in life, you believe that MCSG is real life, and these people are the ones you will know for the rest of your life.
Personally I am tired of building important relationships over the Internet. People leave communities so often that making friends can never be a smooth process. Leaving my personal emotions out of it, "social networking" zaps people out of what's actually important in life. I have seen it become an addiction a number of times. While I do agree that if used casually, it's just a fun experience, some people cling to it.
I love MCSG, Skype, Teamspeak, etc. but I know that it's not the most important thing in my life. Knowing that is what sets the line between playing casually and religiously. I just wanted to get my opinion out there
.