Diigo (pronounced “deego”) is a brand new social annotation site. Social annotation is “a superset of social bookmarking,” the site (www.diigo.com) says. It is similar to del.icio.us in that it is a social bookmarking tool, and even uses the del.icio.us API to give users the ability to simultaneously tag sites on both their Diigo and del.icio.us accounts.
The key differentiation between Diigo and del.icio.us is in the specialized annotation features of Diigo. Users can highlight specific paragraphs or images on a page and post either public or private sticky notes that can be shared with other users who can choose to respond to your sticky notes. These annotations can be saved for later review and can also be forwarded through e-mail.
This further capability and functionality of specialized annotation features is primarily achieved through the Diigo toolbar. The toolbar allows the user to search through numerous resources and also allows the user to bookmark sites of interest. The Inbox on the toolbar lets users keep up-to-date with their tags.
Though this may put Diigo in contention with del.icio.us, these two sites can also be seen as complements to one another. Regardless, it seems that social bookmarking is quickly becoming a battleground that leaves the door open to new competitors with fresh ideas, and that annotation may become a key to success in the arena.
Diigo is currently being tested and is in its beta stage. It is currently available through invitation only, but requests for an invitation can be made by contacting info@diigo.com.
Further information and a detailed tutorial on how to utilize Diigo are found on their website.
Sources:
http://www.eschoolnews.com/
eti/2006/01/001265.php
http://web.corante.com/editorial/
archives/2005/12/diigo_social_annotation.php
http://www.diigo.com/
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