More than one in ten (11%) said social networks have made them expect more from brands and content online, while 14% of respondents believed brands appear more friendly and creative on such sites.
The research aimed to investigate how social networks have become integral to daily life for young people.
Nearly half of 18 to 24-year-old social networkers (45%) said that, if they had 15 minutes of spare time, they would choose to spend it on social networking sites, rather than watching TV, reading, talking on their mobile or playing video games.
A quarter of respondents said the rise in social networks has decreased the amount of traditional television they consume.
More than one in ten respondents (12%) spent between 60 and 90 minutes a day on sites such as MySpace, with a further 41% spending between 15 and 30 minutes on such sites.