Snowdon announced on the 95.8 Capital FM breakfast show this morning that Berry was going to replace Vaughan, who left abruptly last month.
Vaughan had presented the breakfast programme for eight years and it is currently the most popular commercial breakfast show in London, with 1.13 million listeners according to the Rajar figures for Q3 2011.
Berry used to present the breakfast show on sister Global Radio station XFM until April, when he moved to the weekend slot on Capital. He started his broadcasting career in TV presenting at Nickelodeon and then moved to the MTV show TRL.
Since joining Channel 4's youth strand T4 in 2004 Berry has presented shows such as ‘Real Stories’, 'Carling Live 24', 'Vodafone TBA' and 'Celebrity Predictions', in addition to T4 movie and music specials.
Berry said: "To be given the opportunity to wake up London every weekday morning is a dream come true on so many levels. I have an absolute passion for radio, I love this city and of course it's no bad thing working alongside the gorgeous Lisa Snowdon. Bring it on."
Snowdon replaced Denise Van Outen as Vaughan's co-host in August 2008.
Richard Park, executive director and director of broadcasting, Global Radio, said: "I am convinced the chemistry between Dave and Lisa Snowdon will make for great radio and that the show will become a must listen for London every weekday."
Industry sources suggest Vaughan only found out he was leaving Capital on 18 November, towards the end of his final show. Global Radio is believed to have wanted someone younger to replace the 45-year-old.
Ashley Tabor, founder and executive president, Global Group, said: "This is a big moment in the history of Capital FM, and we're privileged to have been able to take this momentous decision.
"Over the coming years, I know Dave Berry and Lisa Snowdon will build on what is already London's biggest breakfast show, and can't wait for them to get started in January."
A spokesman for Global Radio refused to comment on whether Berry was going to be paid less than Vaughan’s reported £800,000 salary.
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