Throughout the run of Big Brother 2011, fans will be able to use Facebook to vote whenever housemates are up for eviction and the standard voting lines are open. Viewers can place up to 500 votes per eviction on the Big Brother Vote App on the show's Facebook page.
The new app, announced on last night's Big Brother's Bit on the Side on 5*, will use the Facebook Credits payments system, with votes costing around seven pence each.
Channel 5's partnerships director Agostino Di Falco said: "We're very pleased that via Big Brother, we are the first broadcaster in the UK to use Facebook Credits as a voting mechanic.
"This fits very well with our ambition to retain the core essence of the show while adding relevant points of innovation which add value to viewers and potential marketing partners alike."
Facebook's director of platform partnerships Christian Hernandez added: "On a daily basis we see millions of people engaging with their favourite TV shows via Facebook. Producers like Endemol and broadcasters like Channel 5 are discovering new ways to expand this engagement.
"The Big Brother voting application is an innovative way for viewers to support their favourite contestants via Facebook and we are excited to see Endemol and Channel 5 bring it to market."
Endemol has introduced social voting with broadcaster RTL for the series of Big Brother in Germany, again involving fans purchasing Facebook Credits to vote on the eliminations (with Facebook taking 30% and the content owner getting the remainder).
Hernandez recently revealed that 10% of the voting on the show now comes through Facebook, suggesting a potential new revenue stream from 'social voting' on popular programmes.
In August, Channel 5 director of programmes Jeff Ford explained the decision to axe the Big Brother live feed, which has attracted widespread criticism from fans of the show.
> Big Brother: Aaron, Harry, Tashie up for eviction
Take a look at the latest photos from inside the house below: