For the CPU required. We just tested the game on an Intel i7-2600 @3.2Ghz, and it works smoothly at 1920*1080. :)

We also tested on an i5, and it worked too, but a bit less smoothly when unning at 1080p. But no problem with lower resolutions. :)

The new voxel renderer will support and use all the threads available. :) So yes, it does take full advantage of 4+ cores. :)