Just as social bookmarking can help you build links back to your website, social networking can do so as well. In fact, it is pretty much common knowledge that social networking profiles are good sources for links for the long term ongoing link building aspects of search engine optimization. But why stop there?
When you use social bookmarking sites like Digg and Mixx (and of course quite a few others), one thing to keep in mind is the social voting aspect of the service. Simply submitting your content might get you a link, but a lot of votes on your content will gain some search traction. Your social networking works the same way, but slightly different.
With social networking sites link LinkedIn and Facebook you are not necessarily submitting links. You are participating and making contacts. But your participation is doing more for you than simply making you a social butterfly. The more you use those services, the more search traction your profile at those services is likely to get. For instance, your Facebook profile might appear in the SERPs but it will appear higher if you are active on the service. The more active you are, the more likely you are to rise to page 1 in the SERPs.
This might be called indirect search engine marketing. It is based on the concept that your reputation rises with the waves. As you build your reputation as the social networks you are also building it with the search engines. And since you can’t have 10 of your web pages on page 1 at the same time for the same keywords, getting your social networking profiles to rank high in the SERPs is the next best thing.