Stephen Downes has a review of several papers about e-portfolios – concentrating on the student use of them, rather than institutional requirements. It’s something that came up at the PLE meeting that I went to – can a portfolio / PLE be truly “personal” if it’s institutionally provide?
The links to Helen Barrat’s ideas about eportfolios are good, though you’ll need to follow Stephen’s links to them, rather than hers in her blog.