This is well beyond my comfort zone of knowledge, but I have to ask. If I throw an electron in, and have "artificial Hydrogen," and then throw a couple more in and have "artificial Lithium" — don't I actually just have Hydrogen and Lithium? That is, what's the difference? Is it simply that I produced this rather than it originating "naturally?" Or is there some other unique property that makes it "not really Lithium" in the lab?

My understanding is that what they did was replicate the electronic configuration of a particular element without having the protons and neutrons there. So they're basically nucleus-less atoms. The difference is that these quasi-atoms are basically immobile (since their position is determined by the positions of the graphene sheets) and thus for example have no temperature. Also they may be able to form covalent bonds, but they'll never form three-dimensional quasi-molecules.

That was a cool watch!