Recently there have been more bisexual women cropping up on network TV, but their bisexuality continues to be primarily fodder for jokes, or only referenced but not actually explored.
In 2003, the CBS sitcom Two and a Half Men debuted with ex-wife Judith (Marin Hinkle) presented as possibly bisexual, but that storyline was never developed, and Judith has continued to primarily date men.
The same year, NBC's attempt at an American version of the hit British show Coupling included Jane (Lindsay Price), who called herself bisexual but really wasn't, and ABC's daytime drama All My Children introduced Lena, a bisexual woman who fell in love with the show's resident lesbian, Bianca — whose best friend Maggie (Elizabeth Hendrickson) has also exhibited bisexual tendencies, although Maggie has yet to actually get romantically involved with women.
In 2004, the lesbian on FOX's Wonderfalls fell for a bisexual woman, but the series was canceled before the relationship could be explored. Later that year, FOX's North Shore introduced a three-episode storyline arc in which one of the show's regular male characters dated a bisexual woman and her girlfriend at the same time.
Although Alex is not a series regular on The O.C., she has appeared in most of its episodes this season, and given the show's immense popularity and millions of viewers, this makes her one of the most visible bisexual TV characters in recent history.
Fortunately, she is also one of the most realistic bisexual characters we've seen on primetime network TV: interesting, intelligent, kind, and a little wise beyond her years. Like all of the other characters on the show, she has her flaws — she stands out as downwardly mobile in an upwardly mobile community, for example — but she's still likeable and sympathetic.
Most importantly, beyond the initial surprise factor, her bisexuality and her (past) relationships with women are for the most part treated fairly matter-of-factly by the writers. So far, at least, the writers have avoided saddling her with the usual promiscuous and non-monogamous stereotypes that afflict most bisexual women on TV (the recent bisexual storyline on North Shore is a recent example).
O.C. creator Josh Schwartz insists that the upcoming relationship between Alex and Marissa is not a ratings stunt, and that Marissa develops real feelings for Alex.
But given Marissa's predominantly heterosexual past, the huge fan support for the Marissa and Ryan (Benjamin McKenzie) pairing, and the controversy The O.C. would court by making one of its principal characters bisexual, it's likely that her "real feelings" for Alex will only last a few episodes.
Regardless of how the relationship between Alex and Marissa plays out, however, integrating a non-stereotypical, openly bisexual character like Alex into one of the most popular shows on television is a significant development, and a long-overdue step in the right direction for network TV.