How Do Links From Social Networking Sites Effect Website Rankings

What about fan-base and followership?

The problem with extracting followership information is, it requires a lot of engineering work to try to extract this data from webpages. In the process, GoogleBot runs the risk of getting blocked from crawling the website. This has happened before once. So Google now tries to avoid doing anything that might get it blocked again from crawling these social sites.

Google crawls the web, and samples it at finite intervals of time, rather than in real-time. The problem with that is, something on a webpage can change after it has been sampled. This happens with many websites, but for most of them, this isn't a problem. Usually, the content change isn't much (or not at all), and Google can pick up that change in the next crawl.

Social sites, however, are unlike most other websites in that they are very dynamic. Content on them changes often. And these changes are important. It doesn't matter much if I add an extra paragraph to a blog post after Google has crawled it, since it's not very important. I can simply wait for the next
update.

But on social sites like Facebook and Twitter, things are much more complicated. Someone could change their relationship status, or block a certain user. So it would be unfortunate if Google crawled a page, and later found out that a certain abusive user has been blocked - it would go against the privacy of the profile or page owner.

This all is not to discourage the use of Facebook and Twitter. You can get a ton of value out of these social networks, as they are a great source of generating traffic, and keeping your fans up to date. But don't thing that Google can index anything on Facebook or Twitter that can form a signal. Pages might be blocked with a noindex, or links may have a nofollow.

So the way to rank well on Google is to create quality content, and establish your identity.