From the Financial Times:
According to Microsoft research chief Rick Rashid, around 20 per cent of all the servers sold around the world each year are now being bought by a small handful of internet companies - he named Microsoft, Google, Yahoo and Amazon. That is an amazing statistic, and certainly not one I'd heard before. And this is before cloud computing has really caught on in a big way. [FT.com | Tech Blog | How many computers does the world need?]
I found this via Nick Carr who goes on to say:
What we're seeing is the first stage of a rapid centralization of data-processing power - on a scale unimaginable before. At the same time, of course, the computing power at the edges, ie, in the devices that we all use, is also growing rapidly. An iPhone would have qualified as a supercomputer a few decades ago. But because the user devices draw much of their functionality (and data) from the Net, it's the centralization trend that's the key one in reshaping computing today. [Rough Type: Nicholas Carr's Blog: The coming of the megacomputer]
I wrote a while ago about Web 2.0 in the context of concentration and diffusion.
Here is the pattern again. We are seeing a progressive diffusion of computational and communications capacity as we acquire more devices (netbooks, gaming consoles, phones,...). At the same time we see a concentration of computational capacity to support the major network services which are so large a part of .our network experience.