After exploring Del.icio.us I feel this Web 2.0 tool can be an effective social bookmarking tool. I really liked the feature of creating a bookmark that provides access from anywhere. This saves time and effort in trying to remember website's address. It has some similar user friendly features as RSS aggregators in that you have everything in one place that you have access to.
As far as using this for research assistance, I feel there are better ways to gather resources. Maybe there is some merit with having your students utilize Del.cio.us to gather information from websites you have bookmarked from home and shared with them. I think this would be more of a tool I would use for personal use than at school.