Here are the 20 Largest Social Bookmarking Sites ranked by a combination of Inbound Links, Alexa Rank, and U.S. traffic data from Compete and Quantcast. Although no traffic metrics are completely accurate we do believe the data below to be useful for gauging relative audience size.
Excellent text that will really help you understand the concept of social bookmarking and the power it holds. The text is straight to the point and easy to read.
A very comprehensive collection of tutorials, advice, resources, tips and tools to help you use Delicious to enhance your marketing, research and other business objectives. There's a special section just for marketers.
"Lijit provides an impressive search network creation dashboard where you can define and manage your trusted social networks connections. Basically you are creating your own search engine that searches your blog, bookmarks, photos, blog roll, and more..."
Chris Moisés suggested this link here. I'm part of the workshop Tony Karrer is talking about, but just as a lurker as I'm really focusing on our online session. However, the great thing of online sessions is that there are many open ones which let you access the resources whenever you want. Next week, they'll be talking about what? Social bookmarking! We're way ahead, huh???