Saving favorites and bookmarks to your browser helps you -- as long as you use that browser and that machine. Online bookmark management makes your favorites available to you anywhere. Social bookmarking makes your favorites available to others. That may sound odd by itself ("why would I want my bookmarks visible to others?") but collaboration is part of the social web and lets people benefit from everyone else's discoveries.
The most obvious library application for social bookmarking (we'll look at Delicious as a prime example) is at the reference desk. Each librarian has his/her favorite online sources and either marks them in the local browser or relies on Google to find them. But suppose each librarian added URLs to a personal Delicious account and then networked with other librarians for a truly collaborative collection of bookmarks. Not only would the librarian make his/her own list available on whichever machine is in use, but everyone in the network could benefit from websites on the consumer specialist's list or the genealogist's list or the music librarian's list.
But don't stop at the reference desk. Other library staff use and share websites, too; introduce them to social bookmarking. And don't forget the patrons. If you have a list of sites to share, enter them into a separate library account and refer to it on your library website or in conversations: "Oh, and don't forget our Delicious site. It has many more great recipe links."
We hope you enjoy your excursion into the social web and open collaboration.