Mariah Carey. Erykah Badu. Gladys Knight. Diana Ross. Olivia Newton-John. Aretha Franklin. Chaka Khan. Great singers. Great songwriters.
Beyonce has a good ability to hold a note. Her vibrato and melisma are notable and her "scat" style of singing was interesting and quite musical. She is a good singer. She has no rasp or edge to her voice though... I absolutely LOVE singers who have that quality to their singing style. Christina Aquillera has a better sounding voice to me personally. She seems to have a greater ability to exert some real pressure on a microphone's diaphragm and has that elusive edge or rasp. Beyonce has been getting serious with her vocal training though... good for her, it really shows in these clips.
Invisibleman made a good point... Beyonce doesn't write her music and will never be another "Aretha, Patti Labelle, or Chaka Khan" simply because she is a TECHNICIAN, not an artist in the true sense. She is a recording "artist" and a member of the musical community, but not a creative artist like Stevie Wonder or Marvin Gaye.
I soooo wish that she would do porn though...