Quick, tell me what Harry Potter, Cinderella (we'll go with the Disney version here, just for clarification's sake), Blair Waldorf, Steve York, Darren Shan, Gemma Doyle, Snow White, and Bobby Pendragon all have in common.
If you said, "Dead, otherwise absent, or antagonistic parents," you get a cookie. Baked by someone other than me, of course.
It seems to me that for years, the role of the parent in a YA novel was to get the heck out of the way. Many parents were, and still are, killed offstage before the opening of the novel, be it by car accident or disease or whatever the author's other favorite method is. I think my favorite parent offing is from Lauren Baratz-Logsted's Secrets of My Suburban Life, in which the main character's mother is killed by a falling pallet of Harry Potter books. Still larger numbers of teens live with single parents and never knew their mother or father, or their parents are divorced. The way a parent disappears in a YA novel isn't really the point here. The point is, they're gone. If the parents are still married, often one or both of them would have an antagonistic relationship with the main character. This could range from a simple existing on two very different planes to one or more abusive parents. In the end, that point remains as well: The parents are somehow emotionally and/or physically separated from the main character. This is a common and even important plot device in YA lit; getting the parents out of the way means that teens are more free to develop as people and have adventures of their own, adventures that they guide, and must face the consequences of their actions without a parent to protect them.
What I'm noticing more and more is a shift from the dead/missing/antagonist parents to teens who maintain a much closer relationship to their parents, and parents who play a major role in the story. Even if one of the parents is dead or missing, the teen will maintain close ties to the remaining parent and have a positive relationship with him/her, or whose improving relationship is a focus of the book. Some examples:
Impossible by Nancy Werlin
My Most Excellent Year by Steve Kluger
Life as we Knew It by Susan Beth Pfeffer
The Mother-Daughter Book Club by Heather Vogel Frederick
There also seem to be many more books of late where it is the actions of a parent rather than the main character or a peer that set the book in motion. Some examples:
Madapple by Christina Meldrum
Me, the Missing, and the Dead by Jenny Valentine
The Last Exit to Normal by Michael Harmon
Cures for Heartbreak by Margo Rabb
How it Happened in Peach Hill by Marthe Jocelyn
Some books focus on a child's/teen's relationship with another significant adult and adults in the story outnumber the main character's peers, like in The Canning Season by Polly Horvath, What I Saw and How I Lied by Judy Blundell, Hope Was Here by Joan Bauer, or The Day My Mother Left by James Prosek.
The other place I'm seeing this parent-focus phenomenon? Television. Gossip Girl and 90210 both give the parents of the teen main characters their own romances and storylines. I'm not saying that parents don't have lives, of course, because that would be ridiculous, but I find it a little unusual in shows that the network is marketing so heavily to teens. In the previous 90210 incarnation, we almost never saw Jim and Cindy Walsh. When I read YA as a teen I always wondered where the parents were, because my parents would never have let me get away with half the adventures those characters had. In all of this I have to wonder: Where is this trend coming from. Maybe it's a reflection of Gen Y's better relationships with their parents? I mean, I don't know about the rest of you, but my Gen X self had exactly one friend in high school who considered her mom her friend, and we all thought she was weird. My Gen Y patrons, however, seem to be much closer to their parents and their parents exercise much tighter control over their lives. It would make sense, then, to reflect this in their literature, but does this mark the beginning of a fundamental change in how teens come of age in YA lit?
Even though Gen Y has better relationships with their parents than previous generations, I don't see the dead/missing/antagonist parent plot device disappearing any time soon. It's still the quickest, easiest way for teens to establish and maintain independence. What I do see is a change in how a teen's story develops, because parents are such a strong influence, for good or bad, in teens' lives. It'll be interesting to see where this trend goes.