Still no real fix for that problem? :/
Most of the symptoms seem to indicate a problem with power for USB devices. Coincidentally earlier this week I managed to hang W8 while booting by having a USB Flash drive in an unpowered USB hub (I was trying to save wear and tear on my laptop's USB ports).
As soon as I pulled the unpowered USB hub I was able to boot without any problem.
I would say its more of an issue with w8. I have had mouse and keyboard work fine in bios and as soon as it boots to windows I loose them. Never had the issue with Windows 7 and my issue started 3 days after upgrading.
The issue is always the same for me and to solve I remote desktop in to the PC, go into device manager and uninstall the following
Intel(R) 6 Series/C200 Series Chipset Family USB Enhanced Host Controller
Then right click and do Scan for hardware changes. This reinstalls and my mouse and keyboard comes back straight away.