Five simple reasons: Apple, Google, Amazon, Facebook, and Microsoft.

Bruce Sterling (flickr/webmink, with some fiddling).
Many people use, as a kind of shorthand, The Internet to mean a wide variety of things related to this series of tubes. The Internet could mean the culture made and distributed on the Internet, the LOLCATZ, memes, etc. ("The Internet loves this kind of stuff.") The Internet could mean the infrastructure itself, its speed and distribution. ("The Internet is so sloooow right now.") The Internet could mean the industry that builds it, the consumer and B2B companies that effectively own all the quasi-public spaces through which we traipse. ("The Internet wants to disintermediate blahblahblah.") And there are a thousand other times when we find it easier to say, "The Internet does" or "It feels like the Internet is" or whatever rather than attempt to identify the specific actors of the play.Stacks. In 2012 it made less and less sense to talk about "the Internet," "the PC business," "telephones," "Silicon Valley," or "the media," and much more sense to just study Google, Apple, Facebook, Amazon and Microsoft. These big five American vertically organized silos are re-making the world in their image.
If you're Nokia or HP or a Japanese electronics manufacturer, they stole all your oxygen. There will be a whole lot happening among these five vast entities in 2013. They never compete head-to-head, but they're all fascinated by "disruption."
What will the world that they create look like? Here's what I think: Your technology will work perfectly within the silo and with an individual stacks's (temporary) allies. But it will be perfectly broken at the interfaces between itself and its competitors.
That moment where you are trying to do something that has no reason not to work, but it just doesn't and there is no way around it without changing some piece of your software to fit more neatly within the silo?
That's gonna happen a lot: 2013 as the year of tactically broken bridges.
