I think that the kinds of jobs/tasks/responsibilities that came (grew) with the job break down into about 6 main areas:

Project Oversight - having some sense of the various eportfolio-related projects, both small and large-scale that might be taking place across the institution. So, projects like first year implementations; PDP-related projects; CPD; ePortfolio Coalition research and various JISC projects - as well as all of the little, but often successful module-based uses which we used to inspire others;

Technical Liaison/Development - working with/alongside Pebble Learning, IT Services and Registry to instigate, test, sign-off, specify and disseminate development and upgrade work;

Lead User - most users (even the most prolific ones) tend to use a limited sub-set of PP features. A lead user is aware of the full armoury of tools, understands how they work and can offer expert guidance on how each tool or combination of tools might support development in any curriculum/professional area;

ePortfolio Manager - this draws directly on language used at Pebble but refers to the institutional roles assigned to a person for: monitoring inappropriate use; advising on quota limits; collating usage stats; providing/managing training; advising on eP specific issues such as data-protection;

Strategic Developments -  advising or driving policy and practice in areas related to: progression, transition, partnerships, alumni, professional bodies, accreditation, assessment and CPD

External Representation - JISC, HEA, BECTA, Subject Centres, RSCs etc.