78% of the people who joins a social-networking site joins it for meeting people they either know or want to know. 47% joins them because they want to entertain themselfs, and 23% joins because they want to lighten their harts.

The average time of a visit on MySpace is 29 minutes (9 hours a month total)! Youtube follows up with 17 minutes. Which means people see about 17/3=5 videos each visit.

De grens van social networking ligt bij drie sites · Marketingfacts (pdf)