To some observers, this is looking dangerously like the outdoor sector time forgot - and it is struggling to shake off a somewhat dowdy image of paper and paste and ill-kempt sites on inner-city buildings.
Which is especially disappointing, some observers say, because this could and should be one of outdoor's more glamorous sectors. With continuing fragmentation in TV viewing, billboards are arguably the last of the big-audience broadcast media and they also offer a more compelling creative canvas than any other mass-market advertising medium.
But recent troubles at two of the sector's biggest players, Clear Channel and Maiden (recently acquired by the US outdoor group Titan), while not directly caused by slackness in the roadside billboard market, have merely served to underline the feeling that the medium's oldest formats are also looking the most tired.
There are those who argue that the media owners have only themselves to blame: in recent years, the theory goes, they have managed their inventory poorly. Revenue has been, at best, flat.
The most severe critics, for instance, believe Clear Channel took its eye off the ball last year in this market as Jonathan Lewis, then the managing director of Clear Channel Billboards, prepared to jump ship.
He had been brought under Clear Channel's wing when it acquired his billboard outfit, Poster Mobile, back in 1999. Having served out his time, he left to form his own company again and, thanks to his strong relationships with the landlords on which many billboard sites are located, may yet prove to be a thorn in Clear Channel's side.
Ironically, this could have turned into an opportunity. It was expected that his departure would lead to the emergence of Julie France as a major influence on the destiny of billboards. As the Adshel managing director, she played a huge part in driving growth in the six-sheet market. Following Lewis' departure, France became the group managing director responsible for all of Clear Channel's formats.
But with almost comic timing, France was also forced to resign when she disclosed sensitive commercial information to the wrong customers. In any case, the six-sheet trick will be hard to replicate in billboards - there are fewer underlying factors likely to work in its favour. Selling the medium's merits as a branding medium will be a long-haul proposition. At the moment, if agencies have a big outdoor idea, they tend to visualise it in terms of some of the newer formats available.
Clear Channel has been receiving plaudits for its decision to launch a division called Create to help agency creatives get the best out of the medium. It will work across all Clear Channel formats but, arguably, it faces its biggest challenges in billboards.
And it will be interesting to see how Clear Channel's senior management line-up settles down in the wake of the departure of its UK chief executive, Stevie Spring, back in January after bust-ups with US management. Stability is vital if it is to deliver on recent promises to begin an investment programme designed to improve the quality of sites - and, ultimately, make the sector fashionable once more.
MAJOR PLAYERS: Clear Channel, Maiden, JCDecaux, Primesight
WHAT'S NEW: Interactivity via Bluetooth technology
CASE STUDY - THE ECONOMIST
Client: The Economist
Creative agency: Abbott Mead Vickers BBDO
Media planning: PHD
Media buying: Outdoor Connection
Role of advertising: Position - The Economist as the essential global
operate outside their time zone and share an uncommon interest in being
well and broadly informed
Sector inventory used: Forty-eight- and 96-sheet roadside and transport locations in London, the South-East and regional airport environs.
Other outdoor media: Forty-eight-sheets on London Underground and rail network, plus six-sheets at airport intersections.
Results: Consistent brand advertising over 18 years has contributed towards The Economist maintaining consistent year-on-year growth.