There are a variety of surveys that have been developed to survey the use of ePortfolios in education.
Nathan Garrett's survey in his 2009 dissertation:
http://docs.google.com/Doc?id=dd76m5s2_556vxjhzt6
Electronic Portfolio Student Perspective Instrument (Ritzhaupt et. al.)
http://docs.google.com/Doc?id=dd76m5s2_1108pcsdpfh
Phil Abrami (et.al) (2008) Encouraging self-regulated learning through electronic portfolios. Canadian Journal of Learning and Technology V34(3) Fall 2008. [Retrieved September 13, 2009 from: http://www.cjlt.ca/index.php/cjlt/article/view/507/238] - The end of this article has questionnaires for teachers and students as well as a Scoring Rubric for Electronic Process Portfolios.