I really don't understand the cherry picking of arguments. Someone posts 6 links and you have a problem with one. So what?
Anyways south Africa is definitely not a first world country. Gdp per head at ppp is 13k[1]. This is substantially poorer than countries like Turkey and Thailand that are often considered third world.
Middle income though? Sure.
[1]http://data.worldbank.org/indicator/NY.GDP.PCAP.PP.CD?order=...