Diigo groups are ideal for team research
If you have any need for team-based research, Diigo groups are ideal for you. A Diigo group can be public, private or semi-private.
Pool and organize resources using group bookmarks
When a member of a Diigo group comes across a web page, he can highlight, tag, and share it to the group. In this way, group bookmarks become a repository of collective research. Group members can also vote up bookmarks so important information stays on the top.
Group sticky notes are great for discussion
When adding sticky notes, you can make them private, public, or viewable only by members of a certain group. With group sticky notes, group members can interact and discuss important points right on the web page, preserving the original context.
Group tag dictionary to enforce tagging consistency
The group administrator can define a set of recommended tags for the group to help enforce tagging consistency.
Diigo has recently launched an education version, where you can create class accounts and add privacy settings, so I recommend you have a look at this.
Oh, and for those of you who can’t quite leave Delicious behind just yet, you can synch the two so that whatever you save in Diigo gets automatically put into your Delicious account as well.