The point of the cloud is that nobody has just one computer any more. {ep[;e have a main laptop or desktop, a mobile phone, a tablet and/or netbook, perhaps another portable device, a work computer, plus there are just times that you need to use someone else's computer. Keeping all those in sync is difficult and not really necessary. Do I want all my work documents on my mobile phone? No. Do I want to be able to access certain ones at certain times? Absolutely. Do I know what those certain ones are? No, not really.
So here we are, the cloud has privacy implications but in the end it may be the only real solution for the growing presence of computers in our lives.