The world's biggest advertising agency is in the making as the bosses of US giant Omnicom and France's Publicis signed a merger deal.<br /><br />It could bring rival accounts such as Coca-Cola and PepsiCo as well as Samsung and Apple under one roof raising potential conflicts of interest. <br /><br />But the two chief executives said there would be "strict firewalls" to protect clients' interests. <br /><br />...<br />http://www.euronews.net/