Normally refers to the annual speech given by the President of the United States about the challenges and courses of action for the country.
I use the term to refer to the discussion lovers have over the health and prospective future of the relationship. The need to start such a conversation usually indicates that the relationship is already doomed.
Her: Honey, we need to talk. I'm upset with you shirking our Friday dates to play poker with your coworkers, and we haven't made love in two weeks. Why aren't you putting in the time with me?
Him: (thinking) Christ, woman. I don't feel like having a State of the Union with you right now.