Gisby has been acting managing director since December 2004 when Hazlitt took maternity leave. She has since accepted a role at SMG as chief executive of radio, responsible for Virgin Radio, Virgin Radio Classic Rock and Virgin Radio Groove.
The new managing director, who joined the company in 2004, will also take on the new, pan-European role of vice-president of media, to be responsible for Yahoo!'s content and product innovation.
Yahoo! is looking to work on expanding its next generation of broadband programming, personal publishing, customisation and community services to internet consumers across Europe.
Dominique Vidal, regional vice-president and managing director of Yahoo! Europe, said: "The increasing penetration of broadband across Europe and growing consumer demand for compelling content on the internet offers Yahoo! an exciting growth opportunity in Europe."
Gisby started his career in strategy consulting with the MAC group and Gemini Consulting, before moving on to help advise the BBC on its digital strategy in the late 90s.
Before joining Yahoo!, Gisby worked at Freeserve, now Wanadoo, from 1999 as the director of strategy and new business, moving on to become managing director of icircle.com and the managing director of portals in 2002.
"Jon's new role will help us to further shape the direction of the media organisation and ensure that Yahoo! Europe is the number one choice for consumers and advertisers," Vidal said.
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