Goodbye email. There’s a new way to share in town, and it’s a little thing called social media.

Facebook, of course, dominates social media sharing, and by a pretty large margin, according to a new report published by ShareThis, in conjunction with Starcom MediaVest Group and Rubinson Partners, Inc. The social networking giant accounts for 38 percent of links clicked, more than the combined 28 percent from email and Twitter. Bookmarking, blogs and other services were responsible for the remaining 34 percent of social sharing.

When looking at all content shared on the Web, whether the link was clicked or not, Facebook accounts for 56 percent, up from 45 percent last August, according to data from All Facebook.

Strangely enough, social discovery application StumbleUpon receives no mention in the ShareThis report. That’s odd because services like StatCounter have always pushed StumbleUpon, above and beyond Twitter and just below Facebook, as one of the most used social sites on the Web.

No matter the constantly confusing number crunch, ShareThis still has a lot to say about social sharing that marketers would find value in, especially in regard to influential users.

In a section titled “The Myth of the Influential,” for example, ShareThis notes that over 80 percent of people share content from just one category each month, a surprising statistic that should encourage marketers to focus on reaching a wide audience instead of just a small group of “influencers.”

Thankfully, it is easy to determine what other categories a user might be interested in based on their current interests. Someone who shares links to music or technology content, for example, will also be inclined to share video game content. Similarly, someone interested in parenting and health is more likely to be interested in sports.

Relevance and scale are of utmost importance to the social marketer--you have to reach the right people at the right time, and in large numbers. It’s the golden ticket of social marketing.

The ShareThis report, which analyzed seven billion signals from 300 million users across 1,000 domains, can be found here.