Exactly what kind of shop Nick Hurrell and Neil Dawson are planning is a subject being discussed at length over the lunch tables of adland's favourite eateries.
Thus far, their plans are under tight wraps. Do they want to follow the Anomoly model set up by Carl Johnson in New York? Do they have a secret client who will demand a traditional agency structure? They say it will be "the agency of the future", a conveniently ambiguous description.
There have been similar claims around the various waves of start-ups over the past decade.
Ten years ago, St Luke's was launched as an achingly cool advertising Utopia. A hot-desking communal co-operative with new-age ideals evident from the start. Mother, on the other hand, was all about getting back to the basics of advertising and stripping away the bureaucratic layers of account people, in favour of a leaner account-servicing. Its structure is kept lean and workable by targeting only a handful of big, blue-chip clients. It's not a unique idea (ask Nitro), but it's one that has proved successful many times over.
Five years later came Clemmow Hornby Inge and Miles Calcraft Briginshaw Duffy; agencies that aimed to be a smaller and more independent version of the shops that spawned them (TBWA and Abbott Mead Vickers BBDO, respectively.) These agencies invested in a new model, launching affiliated direct, media, interactive and PR divisions.
Nevertheless, the emphasis at both agencies is on their above-the-line output. And both use traditional structures - creative, planning and account management - to support it. This is still a winning formula, with CHI now estimated at being the 15th biggest agency in the country and MCBD fetching a potential price tag of £27 million.
Still, the advertising world is changing, and agencies are aware that they must change with it if they are going to thrive in the evolving communications landscape.
Mark Cridge, the chief executive of glue London, explains: "Too many recent start-ups have begun with the best of intentions about being media neutral. However, after a few months the temptation to kickstart every big idea by falling back upon what they know best, an equally big TV campaign, becomes just too tempting."
Take Beattie McGuinness Bungay, an agency that promised to deliver media-neutral solutions and to embrace West End burlesque shows as passionately as six-sheet poster campaigns.
Although it's looking at creative solutions for McCain, such as getting the chips sung about in pantos across Britain, the bulk of its revenue still comes from tradtional ads for clients such as First Choice and Heinz.
As consumers' media habits change, a gap in the communications market for a new agency model with media-neutral thinking embedded in its DNA is opening up. Perhaps Hurrell & Dawson will be the first UK agency truly to embrace the kind of thinking needed to exploit new audiences, and steal a march on its more established peers in the process.
DIGITAL CHIEF - Mark Cridge, chief executive, glue London
"If I were setting up a new agency today, more so than ever it would still have digital at its heart. Because, as everyone knows, all media is rapidly becoming digital.
"Big ideas, which get people talking, are more important than ever, and the best people come up with the biggest ideas. Which is why at glue we've always focused on bringing in the most open-minded people we can find from traditional agencies and matching them with the finest digital talent available.
"So the only thing that any self-respecting new agency should be focusing on today is getting the best mix of the best people, starting with the consumer and what they are interested in, then work out how a big idea can help add to the conversations your audience is already having.
"If you could start with TV-sized budgets as well, just imagine how many conversations you could get going then."
CREATIVE AGENCY CHIEF - James Murphy, chief executive, Rainey Kelly Campbell Roalfe/Y&R
"Start-ups have a clean sheet. Their model can be tailored to deliver exactly what clients most value (and will pay for) at that moment in the market. With relentless change in the media landscape, the three areas where agencies will deliver most value are: Creation of brand ideas - always the agencies' strong hand; Effective deployment of the idea - analogue and digital communication strategy, right at the heart of the team; Implementation - the ability to execute the idea across a much broader range of media and contacts.
"To grasp the latter two will require a more dynamic and entrepreneurial set of skills. Agencies have hundreds of brilliant ideas a year - many never come to life because the industry's skills base is too narrow.
"Developments in other markets also show the huge revenue potential in agencies creating their own IP, whether technology-based or in terms of actually owning media channels. A truly radical development for many traditional heads in London's adland."
MEDIA CHIEF - David Pattison, chief executive, PHD
"If I were looking to do an agency start-up now, it would be digitally based with two major strands: in its broadest sense a consumer-facing advertising business and a consumer-facing content business. They would be separate strands, but brought together by the needs of advertisers, media owners and consumers.
"Ideas-generation informed by a mix of media knowledge agents and planners. With creative execution outsourced to a range of consumer groups and in-sourced to a group of advertising creative innovators. Given the breadth that the word media now has, I have to believe that this company will be a media-led business (but then I would say that).
"It would, of course, open up on the same day as a new breakaway that specialises in 60-second branding ads exclusively for ITV, just to prove that no single model is the right answer."
DIRECT AGENCY CHIEF - Jonathan Stead, chief executive, Rapier
"My start-up agency would integrate clients' communications outputdirectlywith their business and financial objectives, as that's the kind of integration that clients want. Commercial insight would be as important as consumer insight, linking the two being the secret to success. It would have one-to-one communications at its heart, as that's the kind of communication consumers want. And it's at the heart of today's 'service'-based businesses.
"For professional integrity, we'd have no predetermined solutions. And no hesitation in suggesting that communications were not the solution.
"In the modern world, clients need broader 3D marketing ideas - bigger than just execution. The agency would unite the thinking of the best business, brand and data people to create fresher, wider ideas. Best-in-class excellence in everything from TV to the online world would be a given.
"As to where the start-up team would come from, I don't mind as long as they are as open-minded as they are talented."