Mickey Maxwell defines it thusly:
Half retro-future, half cultural mash-up, cyberclunk is science fiction that uses anachronism to reflect upon technology's essential inelegance, because innovation, by definition, will always be the worst version of itself. Because it is new, it is flawed. This is the essence of cyberclunk.
I like this idea of creating science fiction with the intention of being anachronistic and mashing up all manner of anachronisms as a matter of world building. The philosophy being that any attempt at actual futurism will inevitably be wrong and so the fiction embraces this futility as a comment, often a humorous comment, on the transient nature of technology itself.