There are many reasons to get more involved in social media sites. Content creation and discovery, lead generation, and networking just to name a few of the benefits. However, even if you’re not ready to jump in with both feet and create fully a engaged presence on popular social media sites, you should still take the time to create and optimize profiles on a number of sites as a way to control more web real estate and, in some cases, create high value links back to your primary web pages.
I contend that the three most important factors for SEO and small business sites are 1) high quality, frequently updated content 2) properly formatted HTML and 3) high quality links back to your site. Social media sites are an increasingly positive way to get some on #3 knocked out.
This idea of creating backlinks to your website is one that gets debated plenty in the SEO world and quickly erodes to a discussion about nofollow links. Without getting hyper technical, nofollow is a link attribute that tells the search engines not to follow a link, thereby not passing any value from the hosting site to the link destination. Nofollow was created primarily to slow spammers from posting links in blog comments and any other place they could for the sole purpose of getting back links. Consequently, many of the links you place in your social media profiles automatically receive the nofollow attributes and don’t carry the weight of twitter PR9 back to you site. Here’s Google’s take on nofollow