I've had many male bosses and two female bosses. The male bosses have ranged from excellent to OK, but no one really bad, just a bit flakey. The two female bosses are night and day though.
My worst boss was my first female boss; she was an overbearing bulldozer who seemed more concerned with building her empire than anything else. She actually drove one of her suboridinates crazy and almost got herself killed by him; he's in prison now.
My current boss, a female, is the best I've ever had. She is a former engineer, so she knows technology, and how to manage projects. She builds strong working relationships with partnering groups. She actually listens to me and acts on many of my suggestions. She knows her subordinates well and figures out how to motivate and reward us for our efforts, especially when we go beyond the call of duty.
She's the kind of boss that I would switch jobs in order to continue working for.