Jason Rollins gave a presentation with that topic at the recent STM Innovations Seminar in London. The video of his presentation has now been made available by River Valley TV, and his slides are here.
Jason talks about some recent trends in reference management software. For him one important new trend is APIs/extensions. I fully agree with him, but we haven’t really seen many tools based on these APIs. Reference managers that provide APIs include Mendeley, Endnote, Refworks, Papers, Zotero and Connotea. The availability of an API has done a lot for the success of Web 2.0 tools such as Twitter and Flickr.
Another interesting topic was brought up in the discussion: should reference managers track difference versions of an article (e.g. pre-print, post-print, publisher PDF)? According to Jason many Endnote users request this feature. Jason is leading the Endnote development team, but also mentions Mendeley, CiteULike and Papers in his presentation. I interviewed Jason about Endnote back in August.