Ella by a wide margin, simply the best: perfect diction, impeccable timing, subtle "bending' of tunes; purity of timber, great swing, ... I could go on ...and on. Next on my list would be Billie followed by Sarah (Sarah had great range and style but I prefer the more direct style of Ella). In terms of the present cast of singers, I like: the sultry Cassandra Wilson; Shirley Horn; Reeves; Krall (earlier albums only, "When I look in your eyes" and "Loves Scenes"); Jacintha (has a nice voice but is a little cool)