Personally, and I don't know why, but I tend to prefer the sound of male vocals - I wonder if there is a scientific explanation (what isn't there one for, these days?) However, I love Plumb's newer songs and I do like some other female artists - Amy Grant was a favorite for years. I also often like couples or other mixed gender bands - can't beat those harmonies.
An interesting question would be what is the difference between leading in worship and performing? I know it when I see it, and the times it has felt like the latter, it was always a woman up front...and yet, I have experienced some of the best worship through music with female leaders who were totally worshipful. In both cases, the women had physical beauty, but their countenance was different, and usually their dress as well. Not advocating legalism but a humble heart is reflected in modesty outwardly as well.