Facebook and Myspace have both suffered a slight dip in UK users with a drop of 5 percent between December and January, according to data released by Nielsen Online.
Before everybody starts to panic, just bear in mind that it is the first time in 18 months that Facebook has been less visited than the previous month. In December, 8.9m UK unique visitors browsed the website, compared to 8.5m in January.
Facebook is still 7 times bigger than it was one year ago though and its performance, even as UK's biggest social networking website, is much better than the competition - Myspace's audience shrunk by a whopping 9 percent to 5m unique visitors.
The number of people joining social networking websites appears to have tailed off and Alex Burmaster, European internet analyst at Nielsen Online, thinks that the big players are getting new users from their competition rather than from non social networking users.
"However, real growth potential lies in the niche networks, those based on a particular lifestyle or interest, such as travel, music, wealth or business.", Burmaster added.
Behind the two big social networking players, Bebo and Piczo have both registered respectable growths with more than 50 percent year on year growth.