The last couple years, I have significantly increased my use of social media.
I don't believe that online social media is a replacement for face-to-face human contact or for a phone call. But it is a good way to stay connected with others between personal visits.
My primary social media sites are LinkedIn, Twitter, Facebook and Flickr. I use each of these channels for a different purpose and to communicate with a different audience: My resume is on LinkedIn; I chat with IT professionals daily on Twitter; I re-connect with old friends on Facebook; and I use Flickr to share photos.
I joined LinkedIn a couple years ago in order to connect with professionals with whom I had worked. I input my resume and built up a network of current and former co-workers. At the time I was building this virtual network, I didn't realize how useful it would be. A few months after joining LinkedIn, I found myself out of work and needing to network. I reached out to my connections and asked people to log in and write their opinions of the quality of my work. The response was overwhelming. Over 30 people wrote recommendations within a few days of my request. Several times, a potential employer mentioned these online praises during a job interview. I ended up finding a job quickly, via networking.
I use Twitter to communicate with like-minded souls in the tech community. As a software developer, I'm drawn to people who share my passion for learning and for technology. Many of the developers I know are also on Twitter. As a general rule, I tend to follow only those people that I've met in person or that I think I might meet soon. I see many of them at conferences a couple times; but our conversations on Twitter help to keep the relationships going between in-person visits.
I'm a pretty passive user of Facebook. I see my kids using the chat feature and I often see long, threaded conversations on the walls of others. About the only thing I do actively and regularly is advertise new blog posts, announce new episode of Technology and Friends, and show off photos I've taken. Despite being passive, I have reconnected with quite a few friends from my past. Many classmates from my high school days sent me friend requests and now I am using Facebook as a communication medium for our upcoming 30-year reunion. Facebook also provides a good way to get a message out to a lot of people in a hurry. Last year, my sister passed away and I was able to widely communicate her funeral arrangements by posting the details on Facebook. A number of people came to pay their respects after reading my Facebook message.
Flickr provides a social media mechanism: You can connect with other users, comment on photos and share ideas; but I don't use its built-in features. Instead I post photos on Flickr and link to them from Twitter or Facebook. Taking photos at a conference or other event and sharing them online is a great way to stay connected with the community. Recently, I have begun to cross-post my photos on SmugMug because this makes it easier for others to buy prints of my photos.
The sites you choose to connect with others online are not nearly as important as the messages are delivering and the connections you are making.