H.Erectus had long been thought of as the only hominid that really spread geographically before modern H. Sapiens. Recent finds (H. Floresiensis) how how much there is yet to be learned.
AFAIK, the Dmanisi hominids have been declared a variant of H. Erectus, but that may change and they may be speciated from H. Erectus, especially if more individuals emerge to flesh out statistical data. They seem different enough phenotypically. It is very possible that they are a derivitive form of an eralier species as the article suggests.
This is a big find regarding the care of post-reproductive/nonproductive indivduals, which is well documented in even the earliest H. Sapiens finds (such as the Shanidar site), but pretty much unknown outside our own species. I think that it was much more widespread than current evidence suggests, but this sort of thing is very hard to determine from the fossil record alone. The only way to do so is to find (as they did here) very old individuals whos poor health made them unable to care for themselves, but who obviously lived for some time in such a state.