In a significant architechtural move away from X86, the 2011 generation of the XO (One Laptop Per Child Project) will move from a VIA C7 CPU to a Marvell design based on ARM cores.
In an updated article at Engadget, the word direct from OLPC is that it will ‘enable two times the speed at a quarter of the power usage. That version will sell for somewhere in the $175 range.’
Sounds like a ARM Cortex A9 MPCore to me.
If the tech details sound boring though, check out a concept they’re touting for XO-3!