Dofollow social bookmarking sites can play a very important role in improving search engine position of your site and your blog posts. The high page rank dofollow social bookmarking sites can also help you to improve the page rank of your site.
Google page rank is not regularly getting updated for last one year, but it is always good to be ready with quality backlinks. Not to forget the amount of traffic these social bookmarking sites can send you on a regular basis.
Generally, our social sharing activity is limited to a few popular social bookmarking sites and we miss a lot of possible traffic from the other social bookmarking sites.
And, if we want a really good position for a particular blog post we must create a lot of quality backlink to that article and these social bookmarking sites becomes really handy to get quick backlinks.