interesting development, but I don't know I would lump SA in with those two economies. That article states they have USD630b in currency reserves & the price of oil won't stay this low for long.
Oil will stay low and keep dropping as long as
(1) China economy continues it's recession/implosion
(2) OPEC keeps putting pressure on higher-cost producers in an attemt to drive them out of the market
(which will FAIL long-term no matter what but might succeed for a few years 'cause they'll just ressurect when pricing gets high enough again).
Oil pricing might get a LOT lower for a while if the Chinese economy starts dragging other world economies down with it.
I wouldn't plan on oil prices rising for a year or two at least, then it'll take some time after that for them to climb again.