Keenan already oversees Emap's magazines, television, events and international activities, but radio stations such as Magic and Kerrang! have until now been in a separate division under managing director Dee Ford.
Emap Radio was heavily criticised and slapped with a record £175,000 fine by Ofcom in June after a number of listener complaints about 'The Bam Bam Breakfast Show' on London's Kiss FM.
The complaints centred on the use of foul language at breakfast and on a prank telephone call, which was broadcast without the victim's consent. Ofcom described the prank as "the most serious case of unwarranted infringement of privacy it had heard".
In a stinging rebuke to Emap's managers, Ofcom concluded they had a "total inability" to impose the correct controls on the show and that senior management "had little control or sight of local management and was not seeing warning signs until it was too late".
The passing of ultimate responsibility to Keenan was described by Emap's chief executive Tom Moloney as an opportunity to increase cross-promotion, shared consumer insight and talent development.
Moloney dismissed any link between the restructure and Ofcom's ruling on Emap Radio and said: "This suggestion is ill-informed and these are two completely separate issues. This is the next stage in the company's development and will improve coordination and collaboration across the consumer facing business. These changes will allow us to develop more new products on different platforms, maintain the relevance and reach of existing brands and develop deeper strategic relationships with key advertisers and partners."
Emap has also appointed its business media chief executive Derek Carter to the board.
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