One of the articles is by a good friend of mine, but I have to say it was a bit odd of Slate to commission two pieces (Spencer Ackerman / Troy Patterson) about Season 3 of Battlestar: Galactica both written by people who haven't watched the earlier seasons. This perhaps explains why both authors so blithely refer to characters played by Tricia Helfer and Lucy Lawless as "robots" which I think is a mistake. There's a long science fictional history of human-esque robots, androids, and cyborgs -- R. Daneel Olivaw, the T-800, etc. -- but the humanoid Cylons aren't like that.
As we know, the Cylons were created by man. They rebelled. Then -- importantly -- they evolved. They look like us. And, indeed, they don't just look like us but (as one sees in the first two seasons) they're biophysically indistinguishable from us. Indeed, they're capable of interbreeding with us. They're not humans, but -- unlike the Centurions -- they're not robots either. When the human characters develop a slang to distinguish the "look-like-us" Cylons from the "look-like-machines" Cylons, they come up with "skin jobs" to refer to the ones who look like this. This, of course, is what the humans call the Replicants in Blade Runner.
The Replicants, like the Cylons, somewhat mysterious manage to have different physical attributes from ordinary human beings while at the same time there's no physiological test that can determine who the Replicants are. Instead, the authorities need to rely on the Voight-Kampff machine to apply a psychological test.
The current season's Iraq parable aside, this sort of thing has long been thematically important to the show. The Cylons are clearly cast in the role of the "bad guys." Nevertheless, the Cylons consistently do recognize the moral personhood of their human adversaries. The humans, meanwhile, refuse to recognize the moral personhood of the Cylons, insisting on calling them (including the skin jobs, contrary to what Patterson writes) "toasters" and otherwise dehumanizing them in the face of considerable evidence that Cylons aren't so different from you or I in many ways. The Cylons' anti-human campaign, meanwhile, is a classic security dilemma situation. The Cylons know the humans don't regard them as persons, and so see a preventative strike against humanity as their only hope for survival.