Google is using more signals than ever before to determine relevant results for their users. Given the rapid rise in social networks it is not surprising that they would use these as signals in their algorithm. Why? Well, googles initial success was based on the fact that they deemed a link to a website as being a vote for that website. In the same way they can assume a facebook ‘like’ is a signal of popularity for that site, a sign that the site is useful (and should therefore rank). Of course not every business will suit having a facebook page but if it fits and you can do it, do it. Don’t forget with facebook you can set a catchy username for your page, think of keywords!
Twitter is similar. If your business has a thousand followers why wouldn’t google be taking that as a positive signal, you must have something to say of interest! Similarly, if somebody ‘retweets’ your tweets then that is a stamp of approval that you are saying something useful.
If your website is built on wordpress there are many easy to use plugins that can integrate the social networks into your site and help you engage a wider audience. I recently added a facebook like feature to a blog site I operate and found the next day that I and ‘6 others’ had ‘liked’ my most recent article. The power here is the potential for viral promotion and gaining some traffic as well as sending signals to google for your organic SERPs.
I have a twitter account and if you want to be seeing my rare but timely SEO tweets you can follow me at http://twitter.com/stevenapier.
In conclusion: You can’t deny the social networks, if its feasible and sensible to do it, then do it.