Why would iOS require total rework to fit? The most important thing iOS brought was the idea, that small touchscreen requires new UI paradigm. I don't see that changing anytime soon. As for the "under the hood" stuff, it already has a lot in common with OS X, and will share even more with the release of Lion.
Apple for one is known to be looking way ahead of "current market".
Chips that are able to put out more power than current netbooks and still fit into smarphones are not too far away, I'd expect those be ready for market in couple years. Handhelds would be phones that could also be used as laptops/dockable computers. Meego and Qt makes it almost trivial to make same apps work on touchscreen and also with traditional monitor/mouse/keyboard. Remember, the OS is not the platform anymore, it's the app ecosystem.
>Apple for one is known to be looking way ahead of "current market".
So was Nokia. So was Microsoft. It is easy get stuck into profitable segment and not to expand in fear of losses.
