Each bookmarking site has its own pros and cons, and it takes meticulous planning and research before one can consider submitting his/her site content to a social bookmarking service.
From the most basic press release to more complex articles, all site content is examined and then the appropriate site is determined for submission. To top it all, since all bookmarking sites require registration, there is no way that any spam links can be generated to or from your site.
Social bookmarking sites are search engine-friendly, and within seven days of submission links start to appear in all major search engines. If you are serious about your site’s Link Building, Ranking and Visibility, then Social Bookmarking is a must.