When I first installed CM7 on my Incredible, I was, without exaggeration, seeing the battery drop by about 50% in two hours. And I could tell something was going on, because the phone was always warm. Nothing appeared to be syncing; like others here, I was seeing display consumption at about 80%.
Thought I would MIUI, so flashed that, but it seemed to bog the phone down badly, and I don't care for the style, so I figured I'd try Chad's kernel before going back to Virtuous. After flashing Chad's kernel, setting the CPU to its lowest minimum and using smartass, the phone seems to be back to its normal tepid battery life (which means never being sure it will make it all day, but generally making it most of the day). Fingers crossed. CM7 is so great...really hope this can be addressed. Because if it could, there'd be no competition--this would absolutely be the best smartphone OS I've used.