This is just wishful thinking on the part of the manufacturers. "Consumers want power! They want specialization!" No, that's almost exactly the opposite of what consumers want, which is low cost and flexibility. Rather, uber-powerful, single purpose devices are the manufacturer's wet dream. They've been pushing that idea since the '90s, and if anything, the opposite has happened. Phones and gaming consoles are now more like general-purpose PCs than ever.
If netbooks die, it won't be due to "technology changes," it'll be due to Microsoft and Intel doing everything in their power to kill them off, despite high consumer demand. This is a short-sighted, greedy move on their part, and if they don't offer what consumers want, then someone else will move in that will. This is why I think Chrome OS, despite its simplicity, will be huge. If nothing else, it'll light a fire under Microsoft's and Intel's feet.