An study of 100 teen bloggers from around the United States found that the vast majority use blogs to nurture relationships with their peers and build a sense of community -- rather than to admit misbehavior. This preliminary study suggests that blogging could be used therapeutically to help troubled teens express themselves in positive ways.
F. Benevenuto, T. Rodrigues, M. Cha, and V. Almeida. Proceedings of the 9th ACM SIGCOMM Conference on Internet Measurement, page 49--62. New York, NY, USA, ACM, (2009)