I know two totally beautiful, very smart women in my own city who have been single for months, in their late 20s and early 30s. My circle of friends includes any number of other attractive, smart women who have spent substantial periods of time single — not just not in a steady relationship, but not even dating anybody casually. (I can think of one who spent, I think, most of a year single in San Francisco. She has a steady girlfriend now.)

On the other hand, I've also experienced the case where someone I wanted to date (beautiful and smart) was single for only a week or two, and I was too late in finding out. Amazingly, this happened during the six weeks when I myself was single! I'm sure glad I didn't end up with her, though. Compatibility was pretty low.