Assessment and Learner Analytics...the Horizon take...

Appropriate metrics of evaluation lag the emergence of new scholarly forms of authoring, publishing, and researching. Traditional approaches to scholarly evaluation, such as citation-based metrics, are often hard to apply to research that is disseminated or conducted via social media. New forms of peer review and approval, such as reader ratings, inclusion in and mention by influential blogs, tagging, incoming links, and re-tweeting, are arising from the natural actions of the global community of educators, with increasingly relevant and interesting results. These forms of scholarly
corroboration are not yet well understood by mainstream faculty and academic decision-makers, creating a gap between what is possible and what is acceptable.

NMC Horizon Report for HE, 2012 (it's a PDF)