Social Bookmarking sites

Since we are now in the social media era or whatever they call it, let’s talk about social bookmarking sites!
The principle of social bookmarking sites is fairly simple. It’s more or less the same as when you bookmark a web page on the browser on your computer. The only difference this time is that you can share your discoveries with the rest of the world.
The best known bookmarking sites are Digg and Del.icio.us. They aren’t the same and work slightly differently. While you can bookmark the homepage or a specific page on a site on Delicious, on Digg you must “digg” videos, images or news/articles.

Most of these sites are not very valuable for SEO people looking for back links as they mostly are “no follow” links that won’t be counted by Google (but should be by Yahoo). But on the other hand they are great to spread the news or let people know about a new site (or simply a site). Digging an article or bookmarking a page could bring hundred of vistors to your site!