Are Social Networking Sites Reducing Activity on This List?

[Ed]

I think the rise of mobile has an impact and many of the social
networks are closed so there is less cross posting of issues. So in
general email is a declining media, but other than that, I don't think
so. In absolute terms, no. In relative terms, yes.

Once email lists use SIOC and join the Semantic Web... everything will
be much better!!   ;)