2) Android tablets have been around at least for 2 years now. Rapid growth of Android tablets would have happened already if it was going to happen at all. iPad dominates now and with Win8 tablets coming, Android tablets have no where to go. Africa? well, I think when those governments stop fighting and creating civil wars and solve their famine and poverty issues and eradicate and prevent diseases like aids and malaria and spend money on books and education instead of guns and tanks, then we can start to talk about Android tablets. And I don't see that happening anytime soon.
Android marketshare is starting to show signs of slowing down and flattening out while iOS and WP are on the rise. It will only be a matter of time before iOS and WP are duking it out for 1st. Besides the 500,000 apps, Android will have nothing else to compete with the MS and Apple ecosystems in the future.