Growing up in the closet means most gay men have a finely tuned "gaydar" that allows them to identify other gay men by picking up on the subtle cues and clues in things such as dress and mannerisms that fly right over the heads of straight guys.
However, the advent of metrosexuality combined with the rising levels of acceptance and adoption of traits normally reserved for the gays - for example, dressing well and being willing to make physical contact with other males outside of a sportsball competition - means that a lot of straight men are jamming that gaydar, particularly in metropolitan areas.
Author Jeffery Self attempts to come to the rescue with a handy manual he wrote titled Straight People: A Spotter’s Guide to the Fascinating World of Heterosexuals. With his book to guide you, you may be able to tell whether or not that cute bear cub in Margaret Cho's audience is Dorothy's friend or her date. Self isn't leaving the lesbians out, either: he also includes chapters on identifying straight women with categories like "single wannabe Carrie Bradshaw" and "adorkable heterosexual girl."
You can watch Self explain his book for himself AFTER THE JUMP...