This issue was described for CRDoid, see solution in second post about Fix Camera stuck: hereHi,
I found that every once in a while the camera app would tell me that it cannot talk to the camera and to restart my phone.
If that happens my battery consumption is going up. (I just didnt really need the camera.
The steeper slope started when i got the message and it got less steep again after i did the reboot.
Not a biggy... if that helps to improve the rom... ;-)