Whether you’re trying to pick up traction for a new blog or wanting to expand your existing blog following, experts agree that book marking your blog posts is a good idea.

If you’re already tagging your posts and not getting the traffic you want, social book marking is a second layer of optimization that is easy to add and improve page rank.

But there are so many book marking sites now.  Which ones should you target?

The top three right now are Twitter, Digg, and StumbleUpon, respectively,with Pinterest climbing to # 5 last month.  Pinterest is worth noting because of its meteorite rise this year to #3 as an overall social site.