Great shot indeed. Though hardly newsworthy I fear to say...
Etosha is a great place. It has a lot of wildlife that is very easy to see, esp in the dry season. The area is very dry and has a lot of waterholes, so in the dry season this attracts a lot of wildlife. These waterholes are mostly situated right next to a "parking area" (no leaving the car allowed) that's easily reachable from the very good road network in the park, so game viewing is easy. Of course it's not a zoo, so some patience is in order like with any safari.
I don't know whether the author respected park regulations (I suppose he did), but since he shot this image after sunset, he must have been sitting next to one of the waterholes next to which a camp is built. Park regulations do not allow visitors in the park (outside the official camps) after sunset (or before sunrise). People found in the park outside official hours (or wanting to enter the camps outside these hours) are heavily fined. For those who want game viewing outside these hours, there are waterholes next to the camps (with shelters behind the camp's fence where a few dozen tourists can sit and watch all day if they want), or one can participate in an organized evening game drive but these leave well after sunset. Hence I gather the author was sitting at one of these waterholes next to a camp, within 5 minutes walking of the swimming pool, large restaurant, the camp shops (souvenirs and snacks) and a large camping site plus near a hundred rooms for guests... and the smell of bbq in the air... So hardly in the middle of nowhere...
Seeing a black rhino at these waterholes is almost guaranteed. Despite black rhinos being an endangered species, Etosha has a relatively large population. A few years ago, I spent two evenings at two of these camp side waterholes, and on each occasion two or three rhinos visited, though around sunset it was giraffes in my case.
Still, it *is* a great shot, but probably a few dozen other tourists were sitting nearby the author, so at least a handful would have gotten a very similar image. I do wish I was among them!
The shot is great publicity for Etosha's wildlife viewing possibilities, and a great memory for the author, but it's not going to win him an award as wildlife photographer of the year.
Wim