Intel has released BIOS 0131 for DH67CF. One of the items on the release notes was fixes related to "monitor sleep states." I thought perhaps this could be a fix for black screen when TV is turned off then on (which I still get occasionally on my systems without HDMI Detective).
I upgraded two DH67BL (core i3-2100t) systems. No problem. Also upgraded one DH67GD (core i7-2600k) system. No problem there either. But my two DH67CF (pentium g620t) systems are bricked for now (currently working with Intel on trying to bring them back).
There are several others having the same issue: http://communities.intel.com/message/140468
At this point I would hold off on upgrading if you have a DH67CF setup.