It seems like the authors of Affinity Online ( deliberately chose to use the phrase “online affinity networks” as opposed to Gee’s “affinity spaces,” but the book doesn’t offer an explanation why. The section that explains the term simply states:

We describe the groups we have studied as "online affinity networks" to distinguish them from long-standing affinity groups and networks that have predated the online world. We call them "online" affinity networks as a shorthand to distinguish them from affinity networks that are primarily grounded in place-based activities and organizations, and we are not implying that they are not "real," tied to face-to-face interactions, or embedded in physical infrastructures.

I’m curious about the distinction in terms, especially as the book references Gee’s work. Time to get in touch with the authors!