While ISBA and key UK advertisers such as Procter & Gamble have criticised the merger for fears of price inflation, the country's biggest advertiser, COI Communications, has come out in favour. Peter Buchanan, COI's acting chief executive, said: "If there is not a merger, there is a danger of continuing the decline happening under the current fragmented arrangements."
However, rival broadcasters were less enthusiastic. Channel 4's commercial director, Andy Barnes, vowed to fight the merger.
"It's anti-competitive and unless the Competition Commission changes the rules on what constitutes a monopoly it can't happen," he said.
The IPA has also expressed concern that a consolidated ITV could use its size to push prices up, but Mark Jarvis, the broadcast director at Carat, pointed out that because airtime is a commodity market it was transparent and could not be manipulated.
ITV confirmed in a statement on Wednesday that Granada's Charles Allen will be the chief executive and Carlton's Michael Green will be the chairman of the merged operation.
ITV has also finally announced a replacement for its outgoing director of channels, David Liddiment. The controller of CBBC, Nigel Pickard, takes up the role at the beginning of next year.
Buchanan said: "At the end of the day it is about good programming, which delivers good audiences."
Pickard, 50, has spent 30 years in the TV industry. Most recently he axed BBC1's Live & Kicking and replaced it with The Saturday Show.
"Nigel is the ideal candidate. He has previously worked within ITV, he has a breadth of experience and is a great team leader," Mick Desmond, the joint managing director of ITV, said.
But MindShare's investment director, Nick Theakstone, expressed regret that ITV had not found a replacement with as high a profile as Dawn Airey, who very publicly turned down the job to join BSkyB.