I've been implementing Social Bookmarking as part of my overall social media marketing and I've been quite pleased with the results in the past several months.
If you are blogging I would highly suggest setting up accounts at the various sites and bookmarking both your own posts and posts of your friends/peers.
According to my Google Analytic reports the traffic to my site has increased by 208%! in just one month.
If you don't have time to bookmark your posts please let me know as I am now offering social bookmarking packages.