...would be in fully wireless enable netbooks. This thing ought to offer enough power to compete against Atom & co but with better battery life.

Nowdays, smartphone class is defined by the sum of all phone features available to the market, in which the CPU has a big role, but not the only one when price is concerned.
So add a 8mpx camera, latest OS, AMOLED capacitive touch screen, GPS, Wi-Fi, 2000 mAh battery and a decent set of applications - and you'll hit the "sweet" 500£ spot.
Sorry, but I don't see a 100£ smartphone coming anytime soon...