We're not just looking at a cheaper notebook computer here -- which will inevitably be a less-powerful, crappier notebook. We're looking at a completely new category of device here, and low cost is just one of the criteria. The netbook also would weigh very little, and have very little bulk. It's something to carry with you when your smartphone isn't enough, and your notebook computer is too much. You'd slip it into your gear-bag and carry it with you whenever you leave the house, or leave it lying around the coffee table or kitchen counter for when you want to Google something quickly.
Low cost is part of the equation -- but only part of it -- because you want this to be a device you're willing to take with you almost everywhere, and you won't do that if the machine costs enough that you have a heart attack if it's lost, stolen, or you spill piping hot queso dip on it.
The other criterion of the Apple netbook: Simplicity. You'll give up the freedom you have with existing Macs, to download and install software from anywhere on the Internet. You'll have to get your software from something like the existing iPhone App Store. But the trade-off will be greater stability -- and Apple will continue to sell full-fledged Macs for the foreseeable future, as long as there's demand for the more open systems.
I expect we'll probably see the first of these netbooks by the end of the year -- definitely by the end of next year. I don't have any inside information on this -- nor, I suspect, does Gottheil. And when this prediction comes true, I won't take credit for it -- any more than I can take credit for the prediction that the sun will rise tomorrow. An Apple netbook is inevitable, given the direction the industry and economy is moving, and given Apple's own multiyear adoption of simplified appliances like the iPod and iPhone.
P.S. Oh, who am I kidding -- of course I'll take credit for the prediction. I'll brag about it shamelessly.
(Via Daring Fireball.)