A Lotta people are using social bookmarking to generate traffic to their sites. Digg it is among the most popular social bookmarking site out there now.But my personal opinion I have more luck using Reddit. You are wondering why I think reed it works better than digg it. The reason is because on reed it you don't have to summarize your article,so basically you leave it to the recipient's imagination.Meaning without being listed on the popular page you can generate more traffic than digg it. So If you are a beginner in blogging I would suggest using reddit as your primary social bookmarking site.