Statistics

According to an I-Safe INC survey of 1500 students in grades 4-8:

42% of kids have been bullied while online, 1 in 4 have said it happened more than once
35% have been threatened while online, 1 in 5 have said it happened more than once
21% of youth have received mean or threatening emails
53% admit to having said mean or hurtful things to others online, 1 in 3 have done it more than once

According to a 2009 AP-MTV Digital Abuse Survey of 1,247 young people:

Young people regularly encounter mild to extreme forms of digital abuse
50% of individuals aged 12-24 have experienced digitally abusive behavior with college aged students (18-24) being slightly targeted more (52%) than teens (47%)
Young people who have been technobullied are twice as likely to have sought out treatment from a mental health professional and 3 times as likely to have considered dropping out of school

According to the Cyberbullying Research Center, in a survey of 2,000 middle schoolers from across the nation:

20% of respondents thought seriously about suicide
19% reported having attempted suicide
Cyberbullying victims were 1.9 times more likely to attempt suicide than non-victims

According to CAFÉ (Cyber Bullying Awareness For Everyone):

Girls are twice as likely as boys to become cyberbullying perpetrators and/or victims

According to Fight Crime: Invest in Kids (2006):

51% of preteens and 35% of teens who’d been technobullied told their parents;
27% of preteens and only 9% of teens who’d been technobullied told a teacher;
44% of preteens and 72% of teens who’d been technobullied told a friend;
31% of preteens and 35% of teens who’d been technobullied told a brother or sister;
16% of preteens and teens who’d been technobullied told no one.