ePortfolios and weblogs: one vision for ePortfolio development

David Tosh is focusing on ePortfolios -- he's just published an excellent overview of the potential for integrating weblogs and portfolios, with in an introduction to the xml structures that enable the exchange of data:
ePortfolios and weblogs: one vision for ePortfolio development(pdf).

"One main strength of the ePortfolio is the ability to alter the dynamics of learning pedagogy, students are actively engaging in their learning not just the recipients of information. Reflecting on what they are learning may help map out future direction."

This is great stuff. It feels like this ePortfolios could really explode in the next couple of years. Everyone seems to be acknowledging the value, and the technology has reached the point where this could be cheap and relatively simple to implement anywhere. My primary question is whether the tools and processes can engage students to the degree that they'll continue using it on their own.