Social Bookmarking Increases Site Traffic

There's no disputing that Social Bookmarking increases site traffic, the more exposure you can get for your site or blog the better. Social Bookmarking sites like Digg or Twitter usually have fairly good places in the google ranking and the more links which are visible related to your site, the more chance of people bumping in to your site have. In some cases, you can have people "digg" your website in return for favourable ratings of their site. I'm not sure whether that's against site rules or not but it seems quite common.

Considering Social bookmarking doesn't cost anything other than a few minutes registering with the site, it's time well invested.