One approach to trying to meet all of the demands for features and functionality in future library systems, is the ongoing work on what I'm calling a Catalog Pull Platform.
With ideas originating in the Lean Startup movement for technology entrepreneurs and that builds upon the success Toyota and other manufacturers have had in implementing Lean Manufacturing ideas; the Catalog Pull Platform is a fundamental shift in thinking about library systems. We are trying to move away from anticipating the needs and then "pushing" services and technology to our patrons and staff to a model that instead identifies and responds to needs and demands for library technology by "pulling" directly from various constituencies in our libraries.
A Minimum Viable Product (MVP) for the Catalog Pull Platform being actively developed through Build-Measure-Learn iterations is Colorado College's new catalog available at http://catalog.coloradocollege.edu/. This catalog uses a Aaron Schmidt design that he discusses in a blog posting, Catalog by Design