This piece from the Economist puts a bright spin on the future, but even if Africa does continue to grow in percentage terms, it's still coming from a pretty low base. Money quote:
African markets are so undeveloped that the opportunity there is still quite small. According to Stanlib, a South African asset-management group, the market capitalisation of the whole continent is just $800 billion, of which South Africa itself makes up $600 billion. The rest of the continent’s markets, in other words, are worth a good deal less than Exxon Mobil. Put another way, China could buy every African quoted company with its foreign-exchange reserves.In other words, Egypt, Morocco, Libya, and Tunisia: Thanks for trying, don't let the door hit you on your way out.
Into Africa [The Economist]