We've had the commemorative 50p piece; will we have the commemorative pounds 10bn extra by the end of the week? The eyes of the NHS - indeed, of the nation - will be fixed intently on the conference podium at Earl's Court on Thursday at 9.25am. This could be a moment of historic significance imbued with almost operatic symbolism: on the NHS's 50th anniversary the prime minister announces that the government is ending decades of underfunding.

Will he do it? Or will he blow it?

The most optimistic forecasts of economic growth suggest that the government could have an additional pounds 50bn to play with by 2000. And Tony Blair reportedly wrote in a judiciously leaked memo to Cabinet colleagues last week: 'We will make sure the NHS gets the extra resources it needs. It needs major investment. It will get it.'

None of which necessarily adds up to a cash handout of unprecedented proportions. The Treasury is not keen for Downing Street to raise the curtain on selected findings from chancellor Gordon Brown's comprehensive spending review, due to be released later this month. So Mr Blair may be restricted to grand assurances that he will do the decent thing by the NHS without bestowing the detail on the conference.

That may make the difference between a standing ovation and polite applause. The politician who has defied the pundits and the record books to remain, for more than a year, Britain's most popular prime minister ever, is not one to pass up a chance of an ovation lightly - especially on so theatrical an occasion and on one of the few issues on which the government is perceived to be vulnerable.

But even if Mr Blair does dazzle the conference with a pledge of specific billions, delegates might regret obligingly rising to their feet in time for the mid-morning television news. Gift horses - especially those stabled at Richmond House - should always undergo a thorough dental examination. Think of health secretary Frank Dobson's apparent largesse with extra beds, which turned out to be rather less than met the eye. Mr Blair's touted 'major investment' for the NHS has been rumoured at anything between pounds 3bn and pounds 12bn over the next three years.

But given the government's propensity to make every announcement several times over, how much of this 'major investment' would be money the service is already banking on? This time last year the media were agog with speculation that the spending review would usher in more NHS charges. Remember Mr Dobson's loose talk at the Institute of Health Services Management conference? Perhaps delegates should wait for Mr Blair specifically to rule out that and other unpalatable measures before they rise from their seats.

Even vast sums like pounds 10bn take on a more modest aspect in an NHS context. The pounds 2bn on top of planned expenditure which the government has already found for the NHS since coming to power has, in the words of Ken Jarrold (see page 19), merely restored health spending to the level it was at in the austere 1950s under Churchill and Eden. It may sound ungrateful - it may hand ammunition to those who claim that the NHS is a black hole, forever sucking in resources - but it has to be said: even another pounds 10bn will do little more than enable the service to keep pace with growing demand.

Yet it would, of course, make a noticeable difference. It would end the erosion of straightforward, basic services in the trusts and health authorities most under pressure. That would do much to reassure the public and calm the 'noise' that so troubles this government's suave PR machine. It would not - at least for long - enable the NHS to provide all the patients who might benefit with the very latest but highly expensive treatments as they become available.

But if that pounds 10bn was the beginning of a continuing commitment, it would mark a turning point in the NHS's history. Too good to be true? Perhaps.