LONDON: Social networking website Facebook is experiencing a slide in popularity among UK members. Latest user figures supplied by Nielsen NetRatings show a slippage of 5% to 8.5 million during January.

Rivals MySpace and Bebo also saw a decline of 5% and 2% respectively.

The fall in numbers could trigger a frisson of concern among UK advertisers in that they may have already missed the peak of social networking's appeal.

Comments Robin Auld, UK marketing director at Domino's Pizza: "It is difficult to determine which social networks will be a flash in the pan. We are hoping that Facebook has long-term sustainability as a marketing tool."

Data sourced from Brand Republic (UK); additional content by WARC staff