Yes, social bookmarking submission is beneficial for generating traffic to your website. It is one of the effective link building strategy. And able to improve your website’s ranking by improving your link popularity.
Some social bookmarking sites like StumbleUpon, Reddit, Digg can really be helpful if you do it perfectly. You are not supposed to just post your website link in those social bookmarking sites. You must create a friends list and followers network there and share your social bookmark with them. If your friends find your posts really helpful or interesting, they will surely visit your website. This way you will increase your website traffic.