Where is the Social in Social Media

Steaming from a class assignment I got to thinking what social media really means to me, and how I use it.
Facebook was started as a tool to keep in touch with friends and family. Twitter was started as a way to quickly keep in touch with friends. Both mediums has drastically changed in their short life. I did join Facebook so I could keep up with my long distant friends. Then I joined Twitter more to keep up with skiers.Joining Twitter has ballooned and I have met some awesome people there.
However, hard to believe, I'm an extremely shy person that hides behind my fun loving, geeky persona. In using Twitter and Facebook,  I have met some people who has helped me (a few special people, thank you). So viewing them as a means of a business tool is hard. Maybe I look to the mediums naively, as I do everything. What they should be, not what they have become.
I have come across people on Twitter that at first seem like average people then they get into talking of a product or service. These people I do not follow. I find is very intrusive. On Facebook I did not realize the advertisements until I started using the school computers. Guess I have uber security that block all adverts/spam/useless stuff. However, in our society we have advertising everywhere. Why would social media be any different. Yet, Facebook you do have security that you can block your site to only those you invite. Twitter is more open, reason I don't give out too much.  You can choose whom you follow and can see whom follows you. But what you say is out there for all to see and read. With big business gorilla advertising is taking away what these sites are about or were about - connecting with people with like minded interests. Most of the people I have 'met' post blogs and tweet about their jobs. Yet not so much as I would say 'shamelessly plugging' what the do. Some make you actually want to do what they do. I find this very differently from the others that just tweet about their product or service. Which tunes me out. I do follow some organizations and PR firms to get information about what I'm interested in. I do think the best organizations/products are the ones that openly advertise their Twitter/Facebook pages and lets you decide if you wants to follow.
Networking on these sites I'm still trying to figure out. Do not get me wrong I love the people I have met on these sites. Some of the people I would love to sit down with face-to-face to talk. Networking has always been a large part of business, so extending to this medium is inevitable. It comes down to actually figure out how best to use these mediums for you personally.
This blog has me truly thinking. A very public place where strangers read your thoughts. I just wondering if what I say is interesting to others?