People are like, "Oh, you know, Twitter is a great way to do SEO, great way to build connections." I hear all these people on the sidelines like, "Yeah, really, I kind of like my article spinning robot, thank you very much. That works for me." To this I am like, if you took the time and energy that you invested in some of these lower quality tactics and put them into some higher quality, tactics like social connections, and this is where a lot of folks will stop you. They'll be like, "Social connections? Really, Rand? Twitter? Can you actually get direct links from that? I know you get little tweets. You get more followers. You feel good about yourself, like you're interacting in a community. But do you actually drive real links to your site?"
Twitter and Facebook can drive traffic. But as far as getting backlinks that will help build your page rank with Google, no good. All Facebook links are nofollow, so Google is not paying attention to them. The majority of your traffic will always come from search engines like Google and Yahoo.
You don't get backlinks, sure, and the little backlinks that you do get don't really get counted because most social networking sites are no follow. Still, if part of your target market can be reached through Twitter or Facebook, then you should promote your site through these sites. You don't get backlinks, but you do get traffic.
I think its a matter of making those social networking pages of your site more active and helpful for your site, which could add up to your site reputation..