I am definitely not the first person to have written on this subject and surely not the last. However, recently I experienced the SEO value of Twitter first-hand and felt compelled to share my findings. Unfortunately I don’t have hard evidence to support the following claims, but I do have several theories as to how Twitter has directly added SEO value to a web property that I directly manage.

First, it is important to put Twitter’s direct effect on SEO value into perspective.

As many SEO Strategists have noted, the most popular URL shortening services including TinyURL and Bit.ly both use 301-redirects (permanent redirects) which tell the search engine spiders to both index and pass link value to webpages sent in Tweets with URL shorteners. This is a great thing! However, the downside is that Twitter utilizes the nofollow attribute on user submitted hyperlinks which tells search engine spiders to ignore the hyperlinks. Yahoo! and Google search spiders follow nofollow links, but exclude the links from their ranking calculations. MSN (Is it cool to call MSN Bing now?) ignores these links completely. Simply put, links shared on Twitter will not be counted as added backlinks for your website in three of the four major search engines – Yahoo!, Google and MSN.

So what is the SEO value of Twitter?

Ask.com passes link value on Twitter! Woohoo. Ask.com follows links using the nofollow attribute. Many people are quick to write off Ask.com as a major player in search. Why care about a search engine that has just under 4% search market share? Well, it is important to remember that a 4% market share is equivalent to about 375 million search queries per month. Depending on your company’s vertical, this could translate into a fairly significant volume of traffic to your website.

More importantly, though, is the added usage data to your website from Twitter users. There has been speculation that search engines factor in usage data when weighting the overall quality of your website, which ultimately effects your rankings. However, last year Google down played this speculation. But with the rise of shared links across social media platforms, I struggle to believe that usage data plays no role in how a website ranks. Examples of usage data variables include referring sites, number of unique visitors, number of page views, time on site and bounce rate. These variables are effected each time you share a link on Twitter and drive new visitors to your website. This is why it continues to be important to know your audience. If you know your audience and know that the content you are sharing from your website appeals to them, you will have favorable usage data. Google in particular has access to this data not only through Google Analytics, but also from users who have downloaded the Google Toolbar and Google Web Accelerator. There has also been speculation that other search engines purchase clickstream data.

Note: I prefer to use Bit.ly to track how a given link has been shared across Twitter. Simply add a plus sign to the end of any Bit.ly link to see the URLs analytics. Example: http://bit.ly/cxIRl+

Perhaps the greatest SEO value that Twitter has on any given webpage happens without you even realizing it. There are countless services that monitor Twitter for links and then aggregate the links in real-time. Many of the most well-known Twitter link aggregators, such as Tweetmeme and Twitturly, rank links based on how many times those links have been shared on Twitter. In other words, Digg-style votes come in the form of tweets or retweets of a link. Not only do some of these aggregators send significant traffic, but many of them do not add the nofollow attribute to the links they aggregate – meaning they pass link value to your website. This is not to say that all such aggregators and applications that monitor Twitter for content don’t utilize the nofollow, but there are countless websites that monitor Twitter for content that pass link value.

Share Content!

While Twitter itself doesn’t have much direct SEO value, the secondary effects of added usage data and passed link value from third party websites are worth paying attention to. Share relevant content that you know your audience will appreciate and share with their followers. As always, content is king!

For further reading on The Power of Passed Links through social media, Fred Wilson has some great data.

This article was originally published on The JAR Group blog in July of 2009.