[gfirob]

First, I have always thought of black as death and it should be avoided as a video background. You should note that Tony's background is darker that he is (in terms of light intensity) and out of focus, which helps to separate him from the background.

If the foreground singers are lit and exposed 2 or 3 stops brighter than the background you are half the way there (Tony also has accent lights in the frame). Green screen can allow you to approximate this kind of separation if you shoot the background with the same lens you shoot the performance, matching the focus distance between the subject and the lens so that the background is out of focus (a longer-focal length lens helps with this).

If you use green screen you can choose exactly what you want that background to be and how the exposure should look, and it is technically simple to do on most editing programs (I use Final Cut Pro X). The simplest solution is a mottled gray photographer's background (cloth) and nice lighting in the foreground, but green screen gives you the most flexibility.