And of course there was discussion of the thorny issue of how to prevent teen pregnancy. Although Palin had said in the Fox interview that, though happy, she wished the baby had come 10 years later — and that abstinence was "not realistic at all" — she'd avoided discussion of her views on contraception. Bloggers were less reticent this week.

"If she weren't the progeny of abstinence-only education supporters, she might have been on the pill or using a diaphragm," wrote Bonnie Erbe on USNews.com. On usatoday.com, another wrote: "If 'abstinence only' didn't work in the Palin home, where is it going to work?"

For both conservatives and liberals, the issue is a pressing one because national statistics released in December show the teen birth rate, which had been steadily declining, on the rise for the first time in 15 years.

Some have blamed a popular culture that has recently glorified teen moms, as in the popular film comedy "Juno" and the real-life story of "Zooey 101" star Jamie Lynn Spears — Britney's sister.

But Albert, the teen pregnancy expert, senses that teens today are simply less concerned about contracting AIDS or other sexually transmitted diseases, and thus are being less careful.

And so, he says, Palin can serve as a sort of learning tool. "This is just a great time for parents to sit down at the kitchen table and say to their kids, 'Hey, did you hear about Bristol Palin?"

Advocates for battered women hope similar discussions will arise from the Rihanna case. In the weeks since what appeared to be a police photo emerged, showing the pop star shockingly bruised and swollen from an alleged beating by boyfriend Chris Brown, the air waves and the Internet have been buzzing with the question: "Why doesn't she leave?"

But many victims of domestic violence remain with their abusers, says Toni Troop, communications director for Jane Doe Inc., the Massachusetts coalition against sexual assault and domestic violence.

"It can take as many as seven attempts before a victim of domestic violence leaves a battering relationship," says Troop. Besides, she adds, it's fundamentally the wrong question, because it puts responsibility on the victim.

Sheryl Cates, CEO of the National Domestic Violence Hotline, agrees. "We always seem to go to the victim," says Cates. "After 30 years, we are still asking why does she stay, and not focusing on the abuser."

No one knows, of course, exactly what is happening now between Rihanna, 21, and Brown, 19, who's been charged with two felonies for the alleged assault on Feb. 8. There have been conflicting reports about whether the two have reconciled.

On "The Ellen DeGeneres Show," the host grilled rap mogul Diddy about reports he had lent his house to the couple to get back together. "I don't want any girl out there thinking it's OK to go back to a guy who hit her," DeGeneres said.

And Oprah Winfrey devoted Thursday's episode of her show to "all the Rihannas of the world."

"I've said before, love doesn't hurt, and if a man hits you once, he will hit you again," Winfrey said.

Cates says that whether Rihanna likes it or not, she's becoming a sort of poster child for the cause of battered women.