A Progression That Will End When?

The topic of "hardware" in new new media is pretty interesting to me. Levinson seems to argue that there had been a natural progression from pre-computers to handheld devices to more hi-tech handhelds and so on. But what interests me is what forced all these changes? What made the path that has resulted with Facebook, Twitter, and so much more on our cellphones?

In my eyes there are numerous reasons and causes, but what stands out the most is the crave for smaller and faster. It seems as if everything we have, or every new invention must be working in a direction of smaller and faster. It's the ultimate end. So where do we go now? How small can we get and how fast can we get without sacrificing other items?