I'm having the random reboot issue as well. I've tried wiping the device and installing OS 6 from Desktop Manager. I've also tried wiping and upgrading inclemently from .975 to 6 via the OTA updates.
I've tried shrinking the OS down to just the basic OS (with no user apps except the required software) and I still get the random reboots (in other words, it happens even with no add-on apps installed).
I've tried changing the memory card and even tried it without the SIM card installed all with no luck.
The interesting thing is I've never had a random reboot with a 5.0 OS so I really don't think it's a hardware issue. They just occur with any leaked or official 6 OS.
Agradezco cualquier tipo de ayuda.