I was hired (along with the incredibly wise Cara Lane) to review selected e-portfolio systems through a project sponsored by the Western Cooperative for Educational Technologies (http://www.wcet.info) and the Edutools project (http://www.edutools.info).
They invited higher ed institutions to be part of a consortium and those who joined could vote on what tools were reviewed and they established a framework that encompassed feature sets such as formatting abilities, templates and customizations publish/share options, ability to organize, analysis tools, sustainability, and technical summation. Vendors could see the review and offer feedback, additions, and corrections.
In spring of 2006 we had a face-to-face meeting to share the results (at the beautiful Asilomar near Monterey, CA) and we held two online presentations. See the results at http://eportfolio.edutools.info.