To understand the link value, we must think back to the link value principle statement: “Link from relevant and important sites have always been a great way to get traffic and acceptable for a website.”
How do you rate link from new platforms like Twitter, Facebook to a website?
Essentially, Google treats links the same whether they are from Facebook or Twitter, as they would if they were from any other site. It’s just an extension of the pagerank formula, where its not the amount of links, but how reputable those links are (the company uses a similar strategy for ranking Tweets themselves in real-time search).
Facebook and Twitter links may be treated like any other links, they do still come with things to keep in mind. For example you share your link on facebook, you have to keep in mind that a lot of profile are public. When a profile is not public, Google can’t crawl it, and it can’t fetch the page to see what the outgoing link are. While in twitter, most links are no follow anyway.
Links from twitter or facebook will treat like links from wordpress or .edus or .govs or anything like that. This link different if link from .edu that automatically carries more weight or link from a .gov automatically carries more weight, the specific platforms might have issues, whether its not being crawled or it might be nofollow.