How does useing a social book mark tool increase your ranking?

If you have good articles that get hit on social bookmarks, you will get natural links as well from ppl linking to you.

 

It will help a little bit but not in a huge way. Be careful in submitting too many sites to social bookmarking sites though because they will get you for spam and remove your bookmarks.

 

Social Bookmarking is the Best option For Improve Website Ranking, Website PR and backlink

 

Not sure bumping may thread is a smart idea anyway, delcious won't help you in any kind of direct link value though if you can get good good number of bookmarks in first 3600 seconds, you can make it to the front page of delicious which can do WONDERS to your site/page

 

its for increase traffic

 

It can help increase your site's ranking, if you target properly your keywords in your link's title and provided that the social bookmarking site is dofollow.