@Silas - I am under impression that in short term, alcohol dilates all your blood vessels, making heat easily reach everywhere, which results in you feeling warm and rapidly losing heat if you're in the cold. As long as you have energy to spare, you should be okay, but if it lasts for hours, you freeze to death a lot quicker. So alcohol is better used to warm up once you're already in a warm home.
I am not sure about really long term effects.