A recent New York Times piece covers a lot of ground re: instant messaging use within families, and cites a study from New York University that suggests instant messaging may make it easier for teenagers to discuss difficult topics:

"Teenagers already use online communications to take on difficult topics with one another, said Katelyn McKenna, a research assistant professor in psychology at New York University. Preliminary results from a study she conducted last year, she said, suggest that "they are able to talk with one another about issues that bother them more readily online than when they are talking face to face."

Lissa Parsonnet said that her daughter, Dorrie, is sometimes more open to talking with her and her husband online about difficult subjects, like conflicts with friends, than in person.

"She talks to us as if we're people, not parents," she said."