Show which users have any given document in their library
Allow people to see which users have added a paper to their library.
(Discuss in comments)
This is esential if Mendeley is to act as a social network, and become a key part of my research process. At the moment, it's just another reference management system. Currently, I can see that a particular paper in my library has other readers, but I can't see who they are, and whether we share interests. Allowing users to opt in to sharing this kind of information would be a great addition to Mendeley's features.
Agreed that this would make Mendeley more useful as a social network. Even better would be if Mendeley provided a list of users with similar content in their libraries and then used that information to provide recommendations of papers to read—i.e., Mendeley sees that most of the other users with substantially similar libraries have a certain paper that you lack and recommends that you add it.
Stephen Thorpe commented
it would also be very useful if users flagged which papers they actually had in their actual library, so that copies could be requested under "fair use" terms, i.e., for non-open access articles. Something like, "oh, I see Rod has that article .. I should write him for a copy"
Steve Dennis commented
We're discussing approaches to this internally at the moment. It's a complex issue but not an impossible one certainly. Will update here when we make some progress worthy of mentioning.
I think this is the essential prerequisite for Mendeley's social network to take off. At a minimum I'd like to know if a paper in my library is also being read by my contacts (equivalent to Facebook's "x of your friends like this"), but it would be very useful to see who is reading a paper. At the moment Mendeley's design hinders discovering potential new collaborators.
There are privacy issues, but these should be straightforward. Perhaps have default settings (private for documents added directly to a user's library, public for public groups, private for private groups) and let people decide. Keep the options simple, and be very explicit about what others can see about you. For example, show user profile pictures by each paper, and highlight whether user's readership is publicly visible.