We have had the pleasure of some phenomenal female voices over the last 50 years or so, I am not talking operatic voices though.
It does not matter what you think of the individual, there is Whitney Houston, Celine Dion, Barbra Streisand, some would include Mariah Cary, Aretha Franklin could be included, even Lena Horne.
While all can be considered divas, for me, no one tops this performance. That last note is truly phenomenal.
http://www.youtube.com/watch?v=Rt_jjHAQoJU