The initial version will require a 200 MHz ARM processor. That is, iPaq's and Pocket PC 2002 devices. MIPS/SH3 versions could follow but they would have to be cut down in some way. Basically the problem is that the game is partly written in ARM assembler plus its pushing the pocket pc pretty much to the limits in terms of 3D rendering capability.
Desktop version: certainly possible. The game is optimised for a small display though, and I dont claim the 3D engine competes with the ones for 1 GHz desktop pc's with 5th generation hardware 3d acceleration