This thread is misleading. There is no such thing as a PS4 or Xbox 720 development kit. Ubisoft is just working on titles on extremely high-end PCs.
Threads like this existed back before Xbox 2 and PS3 were announced. Developers didn't have the dev kits for those systems so they used high-end PCs with specs that themself, the developer thought, would be comparable to Xbox 2/PS3.







