I haven't done any standardized testing when it comes to the battery draining, but I purchased a black 920 over the weekend (my wife got a white one), and have been having issues with battery life and heat as well. Like very warm, almost hot to the touch on the back near the camera and on the screen. That was under heavy operation, downloading and setting up the phone. Still, I do not think that that's top-notch engineering, as a device should never get that hot.
Since 1/3 of the people polling said that there 920s are fine, I will be exchanging mine today for another unit. If I get the same behavior, I will be returning the 920 indefinitely. I don't think that as consumers, that we should be compensating here. It's more of a mental drain than anything to have your phone on the verge of dying or losing battery constantly, because in this day and age a lot of our livelihood exists in that little piece of technology. Why should I have the screen at the lowest brightness all the time, no background tasks running, no bluetooth, no tap and send, no location on just to get through the day? I don't want to have to think about these things, and that's what makes me miss how most Apple devices are: not having to worry about battery life or toggling settings to making the percentage higher, or battery saver modes, it just worked well and worked long enough.
I'm not sure if this is a color issue or just a phone issue, because my wife's white one has been having better performance than mine (but there are others on here reporting similar problems with other colors as well).