No. The search engines can look at the source of a link and weight it differently from others. For instance, a link to your site from CNN.com is better than a link from SomeDumbSite.com (in theory). So, if two sites are equal in every respect except that one has a link to it from the home page of CNN.com, and the other site has a link from SomeDumbSite.com, the first site will perform better for relevant keyword searches. If you've had your site posted to thousands of bogus link farms (sites designed to artificially inflate Link Popularity) don't hold your breath. Bottom line: attain as many relevant and credible links as possible and don't count on shortcuts.