The linkage tool is a powerful solution for finding out how many different website's have a link on their site that points back to your site. Why is this important? The more sites which contain a link to your will result in a higher 'link relavancy,' which in turn will give you a better ranking in some of the major search engines which use this option for indexing sites.
Now you can easily find out if you need to improve your 'linkability' or if you're doing well. A powerful feature that will help you increase traffic to your site!