The latest Locus Roundtable discussion looks at the work of Greg Egan:

Paul Graham Raven: “Posthuman” implies a transcendence of humanity, certainly, but the whole point of the posthuman as a trope is to reimagine the familiar (namely ourselves) as having the potential to become the alien; it’s about immanence. If Egan’s posthumans were any more post-, they would stop being recognisably human and simply be aliens. The implied continuity between reader and character is the core rhetorical thrust of posthuman sf; as such, I’d suggest that to complain that Egan’s posthumans are recognisably human in origin is to misconceive his entire project.

See also previous discussion around these parts.