According Wikipedia the term of virtual ethnography means:

(...) Online ethnography or Virtual ethnography ‐ also called netnography for a decade in the business, marketing and consumer research field (Robert Kozinets 1997) and more recently webnography (Anjali Puri, 2005) ‐ is a new development in the field of Ethnography.

Online ethnography is an online research method. It extends the traditional notions of field and ethnographic study from the observation of co‐located, face‐to‐face interactions, to technologically mediated interactions in online networks and communities.

In doing so it challenges the traditional notion of a field site as a localized space and moves it into the realm of online or computer‐mediated communications and interactions. (...)

(...)The term netnography has gained currency within the field of consumer research to refer to ethnographic research conducted on the Internet. It is a qualitative, interpretive research methodology that adapts the traditional, in‐person ethnographic research techniques of anthropology to the study of the online cultures and communities formed through computer‐mediated communications (“CMC”).

Source: http://en.wikipedia.org/wiki/Virtual_ethnography