40-year-old Davina began her presenting career in 1992 on MTV. She was spotted by ITV in 1995, who signed her up to present gameshows God's Gift and Don't Try This At Home. Channel 4 then gave her the job of hosting dating show Streetmate.

In 2000, she became the main presenter of Big Brother, and has fronted almost every series since. Last year, during Big Brother 8, she also hosted spin-off show On The Couch, which was later dropped.

Her other presenting credits include Popstars: The Rivals and He's Having A Baby, as well as her own chat show. In addition, she has taken part in Comic Relief and Sport Relief telethons for the BBC, and she guest hosted a Christmas edition of The Friday Night Project in 2007.

George and Zezi joined the Big Brother presenting team in May this year as the new faces of fanzine spin-off show Big Brother's Little Brother, after Dermot O'Leary left the show in January.

Both have presented Freshly Squeezed, Channel 4's morning music programme, and E4's music strand E4 Music.

George is known for hosting a radio show on BBC 6Music during weekday mid-mornings. He also works on Channel 4 programming strand T4, and has managed music acts such as Lily Allen and the Audio Bullys.

Zezi is part of a DJ duo, named 'Zapotecsoundsystem', which she formed with fellow E4 Music presenter Nick Grimshaw. She was once editor of cult fashion magazine Super Super, has worked in A&R for Universal records, and has even tried her hand at becoming a stylist.

Iain Lee and Gemma Cairney are new additions to the presenting team for 2008, hosting Big Brother's Big Ears, a spin-off radio show broadcast twice weekly on the Official Big Brother Website.

Iain has a history as a radio presenter - he has presented a Sunday night show on Virgin Radio since January this year, and was previously a host on LBC 97.3. He has also had a number of television roles.

Gemma has also had a radio presenting history, having hosted a number of show for Channel 4's online radio arm 4radio. She was previously a stylist for acts including Sugababes and The Pigeon Detectives.

Marcus is a 40-year-old voiceover artist. He was born in Gateshead and brought up in Stockton-on-Tees, and has a very deep 'Geordie' accent, which makes him one of the most instantly reconisable voiceover artists on British television.

He became a continuity announcer for Channel 4 in the late 1990's. In 2000, he was given the job of narrating Big Brother highlights. He was chosen because the producers liked the way he says 'chickens'. He has narrated every single series of the show since.

Other credits include Sky One gameshow Dirty Money, which he hosted by voiceover. He is also an actor, and has had bit parts in The Bill and London's Burning.