By living in New York, I have learned that black is part of the New Yorker's everyday uniform. But I am from the south and have lived all over the world and like to mix things up a bit. If I do wear all black, I always add a streak of color (e.g. black pants and shirt with bright yellow shoes).
I love wearing all black, but I usually break it up with bright shoes, belts, and/or other acessories. Black can take you from day to night without having to change; plus pretty much any MU looks good with black.