The fourth season of Australian Idol first episode aired on 6 August 2006 and concluded on 26 November.

Changes for the fourth season of Australian Idol included the cancellation of "Inside Idol"; a "streamlined" semi-finals (replaced with a variant of the 12 females, 12 males format popularized by American Idol); and the contestants will be able to bring instruments with them on stage for at least one of the final shows. Also, the fourth season's television promos promised a change in the viewer's role in the show, revealed to be an SMS service called 199-JUDGE which allows viewers to SMS their opinions on the judges' reactions.

The show opened with average ratings (1.4 million) that were on the whole up from last year's ratings. The semi-final shows averaged 1.5 million viewers per night; the ratings remained constant until the Top 8 show, which averaged 1.89 million viewers, much higher than any of the Top 12 shows last year, and was the most watched show on Australian television for that week. The Top 7 Show, which was "acoustic night", was watched by even more - 1.92 million. The final was watched by over 2.1 million people. The audience peaked at 10.13pm (Australian Eastern Standard Time) attracting 2.4 million viewers.[2]

Australian Idol is an Australian singing competition, which began its first season on July 2003 and ended its run in November 2009. As part of the Idol franchise, Australian Idol originated from the reality program Pop Idol, which was created by British entertainment executive Simon Fuller. Australian Idol was televised on Network Ten for all seven series, and was broadcast on Austereo Radio Network between 2005 and 2007.

Australian Idol sought to discover the most commercial young singer in Australia through a series of nationwide auditions. The outcomes of the later stages of this competition were determined by public voting. The original judging panel featured Mark Holden, Marcia Hines and Ian Dickson. In 2005, this was changed as Ian Dickson was replaced by Kyle Sandilands.

In 2007, Ian Dickson returned to the program, when Mark Holden left at the end of the season. In 2009, Kyle Sandilands was replaced by Jay Dee Springbett. Network Ten made the decision to "rest" the program for 2010, supposedly due to a clash with the Commonwealth Games.

Dean Stanley Geyer (born 20 March 1986) is a South African singer-songwriter and actor who came third in the 2006 season of the talent show television series, Australian Idol.

Dean Geyer was born in Johannesburg, South Africa, as the oldest of three children to parents Debbie and Keith. He has two younger sisters, Jessica and Tatum, who share his interest in martial arts. He moved to Melbourne, Australia, at age 15 leaving most of his family behind. Dean attended Melbourne High School, a select-entry school for boys, finishing his Victorian Certificate of Education from MHS in 2004, but did not pursue higher education, as he was by his own admission, "not made for school". Geyer's interest in music started early in his childhood. He learned to play the guitar, and wrote his first song entitled "Change" which was based on his move from South Africa to Australia. At his Australian Idol audition, he played a self-composed song called "Nice to Meet You".

In 2004, Dean Geyer formed a band called "Third Edge" and recorded his original music at Studio 52. Studio 52 then permitted Dean and his band to perform at the Kool Skools awards night, but they only received a nomination.

Jessica Hilda Mauboy (born 4 August 1989), is an Indigenous Australian R&B singer, songwriter and actress. In 2006, Mauboy was the runner-up on the fourth season of Australian Idol, she had auditioned for the talent show in Alice Springs to pursue a recording career. Mauboy subsequently signed a contract with Sony Music Australia.

In February 2007, she released her debut live album, The Journey, which reached number four on the ARIA Albums Chart, and was certified gold by the Australian Recording Industry Association (ARIA). The album contained selected songs Mauboy performed as part of the top 12 on Australian Idol. Later that year, she briefly became a member of all-girl pop group Young Divas, before resuming her solo career early in 2008. Mauboy released her debut studio album, Been Waiting, in November 2008, which spawned her first number-one single, "Burn", as well as the album's other top 10 hits, "Running Back" and "Because". In 2010, Been Waiting was certified double platinum by the ARIA, for shipments of 140,000 units, and became the second highest-selling Australian album of 2009. At the 2009 ARIA Music Awards, Mauboy earned seven nominations for the album and singles; she won 'Highest Selling Single' for "Running Back".

Damien Leo Leith (born 18 January 1976 in Dublin) is an Irish Australian singer–songwriter. He was the winner of the Network Ten music contest Australian Idol 2006.

He was born in Ireland and now lives in Australia with his Australian wife, Eileen Stapleton, their two sons, Jarvis Dion (born 2005) and Jagger Ramone (born 30 May 2007) and daughter Kikki Bo (born 27 March 2011). Leith became an Australian citizen on 25 January 2007, taking the pledge from then Prime Minister of Australia, John Howard, in a nationally televised broadcast on Network Ten.

Leith was a contestant in the 2011 season of the Australian version of Dancing with the Stars on Channel Seven. He made it to the final three dancing stars before being eliminated. His early years learning Irish dancing were an asset which made him light on his feet. Leith reportedly lost 10 kg during the taping of the show.

Leith was raised near Milltown, County Kildare. His father travelled as part of his work as an engineer, and their family lived in countries including Libya and Botswana.