To be Bi Curious means that a person has a strong attraction to people of the same gender, but have had almost no sexual experiences with them.
There will always be groups and individuals who claim that any sexuality other than heterosexuality is wrong, sinful or goes against evolution -- it is my personal belief based on a philosophy revolving around the importance of love and communication that in fact, being Bi Curious is the only true perfect form of sexuality.
A person who is Bi Curious can feel a sexual attraction to both men and women, and as such has the ability to form a romantic and, in time, intimate relationship with anybody they so choose, regardless of gender.
This means that as a Bi Curious person you can fall in love with your true romantic counterpart -- something not everyone can do. We are, at the end of the day, not our bodies. Our bodies are shells and vehicles storing our brains -- our gender, or rather that of our “vehicle” is not relevant in terms of love; after all, if the brain of a 5 year old were placed in the head of a 60 year old, the person would still be 5 years old.
It is for this reason that being Bi Curious goes with evolution; we are smart enough to recognize that love between two people goes beyond the ability to procreate -- thus, it is the only sexuality to celebrate the true nature of love and attraction based on a deeper and more intelligent level than purely sexual.