Building incoming links can help you boost search engine rankings. But note all links does not create incoming links to your website. Before spending time creating links in high PR site, it is worth while seeing the links are do follow links or do not follow links. Do not follow links does not help with any SEO but of course if the links are in high targeted sites it can help with increased traffic.
So if you are looking to create links for link building activity, we recommend that you download the firefox plugin NoDoFollow. This can save you sometime. With this plugin installed in your browser, by simple click of the mouse you can find out if it is worth creating links in that website.