Nvidia´s chipset boss has confirmed that the company is on track to start shipping its Ion 2 chipset in 2009. He didn’t go into details telling about any specific designs as this depends on the customers.

The next generation Ion platform does support different Pentium 4 compatible processors, including VIA Nano and naturally Atom,  as well as some ultra low voltage stuff. The future CPUs such as Arrandale Core i5 based mobile stuff won't be compatible as this is a DMI chipset, something ION cannot support. 

The support for VIA is there, but this will depend on the customer as if customer wants it, the possibility is there.

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ION 2 has 2X+ more shaders