Thoughtful critique of so-called ethnography usage in design

A very relevant and thoughtful critique of so-called ethnography usage in 'designing user experience' can be found on Rashmi Sinha's blog (about the DUX conference):Many speakers told us about the "ethnographic research" they conducted. Sometimes they shared some video of their observations - of children playing, or people in their homes, sitting on a chair, or watching TV. And the audience would watch delightedly - look at that, its people! People playing, laughing, sitting, walking... It all seemed very rosy - "we observed some people, maybe for a few hours, maybe we lived with them for a week or two - they still send us postcards - the dears. And at the end of it, we had the Aha moment, when it all fell into place. And the product was born." And everyone lived happily ever after. (...) I doubt that most people are even doing ethnography in the real sense of the word. Call it user/customer research, observation / qualitative interviews / design research. Sometimes when talking to clients, they ask us if we do "ethnography" - I always say, "well kind of", feeling guilty about calling the type of qualitative research that one has time for - ethnography.

Why do I blog this? It's as if ethnography was now a buzzword referring to taking picture or videotaping people doing something and then concluding about the phenomenon. With the exploding number of papers, studies, or conference about the use of ethnographical methods in design/business, there seems to be now some confusion. Besides, I like the author's emphasis on the constraints because I have the same problems in my work:

there are many challenges remaining - how do you make sure that the insights in the observer's head reach other members of the product team (...). How do you synthesize those insights? How do you go from that synthesis to the product concept? And how do you validate those product concepts - make sure they generalize beyond the few people you were able to observe?