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I wouldn't be surprised if "majority of people" hasn't ever even used a desktop computer. At the least, "majority of people" probably doesn't use them very often. So when it comes to "will still need a desktop computer"... (emphasis mine)
OTOH, there are over 5 billion mobile subscribers. Most on so called "dumb phones" or "feature phones" at this point (still, they often are not only the first real means of distance communication, also of internet access), but inexpensive Chinese Androids are coming (or, possibly, their forks of Android; which might be not a bad thing, they might be better optimized for the developing world)...
...and I won't be surprised if/when they will eventually take the form of "small tablets" or "large smartphones" (but without the ridiculous premium such models have in developed markets). Less duplication, less waste, less cost (especially important here); and it would finally give real purpose to Bluetooth headsets (and less reasons to get into desktops, for many people)