By Nick Higham BBC media correspondent

The news about advertising revenue could be getting better.

Granada's announcement last week that Maureen Lipman was joining the cast of Coronation Street could not deflect attention from the company's dismal results: a pre-tax loss of �169m in the six months to the end of March, thanks largely to the ITV Digital debacle and a year on year fall in advertising revenue of 9 percent.

But Granada - and Carlton, which announced a loss of �180m a few days earlier, and a decline in ad revenue of 13 percent - profess to see signs of an upturn in advertising. The current three month period is apparently the first quarter to show an increase in revenue for two years.

Coronation Street: Granada is seeing more in its tills

Much of that, of course, is due to the World Cup, which traditionally proves popular with advertisers of things like beer and cars which appeal to men.

The real question is whether the current upturn can be sustained once football fever has abated: revenue was up more than 10 percent in May at both Carlton and Granada apparently, but increases for June and July are more modest.

Elsewhere the noises coming out of media companies are less encouraging. John McGuckian, chairman of Belfast-based UTV, says that despite a short-term improvement "it would not be prudent to signal a possible upturn".

Daily Mail & General Trust - which has significant interests in commercial radio as well as the Mail and a stable of regional newspapers - says it's planning on the basis that ad revenue won't improve this year.

Carlton's chief exectutive Gerry Murphy: Recently announced a loss

Radio group GWR (27% owned by DMGT and the subject of speculation about a possible merger with Capital) said income had increased slightly in the first months of the year, but believes it is too early to be sure if there is a sustained pattern.

Likewise Emap, another major radio group: "The market is still tough and we have nothing to be complacent about," in the words of its chairman, Robin Miller.

Scottish Radio Holdings says national advertising is not expected to recover until next year.

So when Carlton and Granada announce they are putting more money (an extra �25m) into programming it is something of a gamble.

So too is the two companies' gigantic and innovative four-year deal with Unilever, one of Britain's biggest advertisers.

Missed deadline: The Daily Mail's parent firm is pessimistic

This is said to be worth �320m - a substantial sum. But industry rumour suggests that Unilever has been able to negotiate a substantial discount and that the final figure paid may depend on ITV's ratings performance.

If ratings are poor, Carlton and Granada may not get all the money.

Given that they are also having to deal with speculation about mergers and takeovers in the wake of the draft Communications Bill, it means that ITV's managers are in for a potentially torrid time - just when they might have hoped to get back onto an even keel in the wake of the ITV Digital debacle.