I'm sure there are more black people with money in South Africa than there were twenty years ago - but the overall situation of the black population hasn't improved significantly. If anything, they may well have become poorer, with their household incomes falling as those of the rest of the country rise (1).
So what's happening is the creation of a small black economic and political elite, with wealth and privilege comparable to the upper echelons of white South Africans; but no overall improvements in the lives of the vast majority.
It can't be long, however - he's in his 90s and looking very frail. Expect a full Diannafication when he goes, though.
1 - "Voice of the unpeople" by Mark Curtiss. Published in The Guardian, 3rd of June 2006. (http://www.guardian.co.uk/books/2006/jun/03/highereducation.news)