Girls and women that is--who will be a more obvious segment of the competitors' pool at the X Games. I have never followed the X Games closely but I do remember that in their early days there were female athletes. Then as time went on they seemed to disappear.
This article in USA Today explains some of the history, which involved numerous cancelled events and competitions due to lack of participants and fewer events overall than in the men's field which really took off. But the S3 Supergirl Event is starting to change that. This year, the event's second, takes place later this summer in Huntington Beach, CA and has snow, surf, and skate events and will feature Olympic and X Games stars.
Supergirl will be creating a line of action clothing and is counting on marketing its product to the up-and-coming actionistas--the term coined to describe female action/extreme sports athletes.
As for one of the original action sports events, the X Games is expanding their program this year to include women's motocross. The event will join women's skating and surfing as the only other contests which feature women.