Facebook is to launch a "public listing service" that will let anyone search for a particular person on the site in huge policy shift for the service.

It's no doubt going to be controversial - one of the major pluses users states for Facebook is that until now, it has always been a site that allowed you privacy.

Although not live just yet (so we can't report on exactly what info is shown in search results) a spokesperson has apparently said the info revealed is "minimal".

"A public search listing provides, at most, the name and profile picture of any Facebook member that has their search privacy settings set to 'Everyone'."

"It will show less information about a person than results of a search performed by someone logged in to Facebook. We wanted to give people who had never come to Facebook, or who are not currently registered, the opportunity to discover their friends who are on Facebook."

A month on from the public listing service going live, the listings will be incorporates into search engine indexes - so Facebookers that value their privacy have 4 weeks to change their privacy setting.

Presumably the move to open up Facebook is in a bid to get more users, who, if finding friends on the site are more tempted to join.