Christmas Day was Facebook's busiest day ever in the UK, according to Hitwise, up 69% on Christmas 2007, presumably a result of family and friends using the tool to contact each other on the big day.

Social networking sites as a whole accounted for 1 in 10 of all UK internet visits during Christmas week, the first time the category has broken 10%, with YouTube overtaking Hotmail for the first time.

It's not such good news for online retailers though - Boxing day traffic declined by 4.9% on last year, whereas the numbers of shoppers who got off their arses and went to the High Street sales was up 12.5% on last year.