In the future our data lives on the nebulous group of geographically distributed server-farms we call 'the cloud'. If the proliferation of computing devices that has been gaining momentum in the last few years continues then we will become more and more reliant on the cloud to make them individually useful. If these devices are all, for want of a better term 'autistic' – then using them in collaboration is an unacceptably onerous experience. If using them is difficult then we simply wont use them.
These tools are becoming very context driven; it's obvious with mobile devices that they offer situational advantages, you wouldn't necessarily want to use a smartphone for all your computing needs but it's often the perfect tool at the time. It's in your pocket. This trend must surely be even more pronounced if the fabled 'wearable computing' transition is truly on the horizon. These devices will logically have even more specific purposes and will likely rely on other computers to broaden and expand on their hardware functionality. The Nike Fuelband is a perfect example: it does a very specific data collection job and relies on another computing device to turn that into something with a broad and useful application.
There will never likely be a one size fits all solution to the cloud storage and syncing issue. While all the major players have an offering, none of them will be suitable for all purposes, storage will remain relatively costly for common purposes (like video, music or photo storage) and some will be tightly controlled to maintain security and/or user experience. It's likely that we will all continue to manage multiple cloud services for the forseeable future.