More than 90% of people still using bookmarking locally in their browser.. other bookmarking tools are not too popular. From the seo point of view i thing it don't worth much.
I beg to disagree If done properly, it can generate tons of traffic plus the links you can get from high pr SB sites.
interesting point of view, I am a "bookmarker" love to bookmark sites I like locally on my pc and use FOXMARKS (firefox add on) to use the same bookmarks form home and from work. However I do use social bookmarking tools, and know that these do give good links back to your site, If I really like an article or page I will bookmark it in a social bookmarking tool so users can see what type of internet surfer I am from the "stuff" I like Also yesterday it was widly reported that social network/bookmarking sites (like facebook etc.) are now are used on the internet more than email. IF i am focusing on SEO and site promotion of course I will use all the social bookmarking sites to help promote the site I am SEOing
Social bookmarking and browser bookmarking are two different things. Social bookmarking is more geared towards (a) making your bookmarks more portable (accessible at work, home and school) (b) Sharing your bookmarks with others. That's where the SEO factor comes in. People who use these services want to link themselves to their friends and others. They want to share their bookmarks, and want to read other's bookmarks. Also they want to find new resources, or share the one's they've found. In that respect, it's a great way to drive traffic, and get inbound links. That's how it helps from an SEO perspective.
social bookmarking can give a site lots of traffic. If used correctly they are a great place to launch a link bait campaign.