Artie Fish is a tremendously interesting creation. He's not an alien creature at all; his motivations are even less odd than those of Wintermute. He comes off as more of a child-figure than anything else, a rambunctious and tremendously intelligent creature loose in the net; at one point, Sam thinks, "It would just figure. The first real, possibly conscious, AI, and it postured." Artie is undergoing what amounts to digital adolescence prior to his strange adulthood, triggered by his merge with Visual Mark.
More importantly, Cadigan, like Gibson, views artificial consciousness on the Net as something that's just going to happen naturally:
"The net system was complicated to begin with," Fez was saying, with a faraway look on his face. "I suppose consolidating everything into the generic commodity we know as the dataline was the start of it. But nothing might have really come of it if it hadn't been for the input that exceeded. So to speak...Like the viruses, and the piggybacks, the floating boards that pop in and out wherever there's space to accommodate them. All the hackers who found a little capacity here and ther and squeezed in compressed data and programs. The hackers who made capacity where there technically wasn't any by using the virtual spaces between bits, and then the spaces between those bits, and the spaces between those."
It's an interesting viewpoint (dating back at least as far as Robert Heinlein's The Moon is a Harsh Mistress): eventually, a complex enough information-processing system will be transformed into an information-processing entity. At what point did humanity's evolutionary ancestors stop being clever tree-dwelling rats and become something more? Will computers ever do the same? I doubt that complexity theorists would appreciate Cadigan's view, but it makes for fun reading and provides yet another bullet in cyberpunk's magazine. The final weapon in the post-Cartesian assault on the supremacy of the meat is that the brain isn't important because people aren't important; eventually we'll create that which will supplant us, and we might not even notice.