ACM Queue has an article by John Canny, University of California, Berkeley:
Let’s start with PCs. Where are they now? Intel recently reorganized itself to align with the major market sectors for Intel PCs today. Those sectors are office, home, medical, and mobile. That’s a lot of PCs in new places, and they’re almost all running a Star-style WIMP interface.
What about cellphones? Global cellphone sales are now running at 800 million units per year, about four times the annual sales of PCs (or television sets). Recent years have seen 100 percent annual growth in overall phone sales, and close to 200 percent for smart phones. Sales are nearing saturation in developed countries, but still accelerating in the Third World, which dominates now. Smart-phone sales are about 15 percent of the market now (around 100 million units), but with their faster growth should outnumber PCs by 2008. Smart phones today are about as powerful as a midrange PC from eight years ago, but they waste the latter in media performance. Although only a tiny amount of smart-phone software is around now, it is one of the fastest-growing sectors of the industry. Unfortunately, if you’ve tried interacting with a nontrivial smart-phone application, you’ll know what an ordeal it can be. There has been a brave effort to evolve it from its WIMP interface roots, but it just feels wrong – like a shark in a shopping mall.