Alastair Hignell column: The genie is out of the bottle and no-one can predict the future with any certainty.

Only time will tell whether the decision to confirm rugby as an Olympic sport from 2016 onwards is, as many would hope, the greatest single event in the history of the sport or, as some would fear, the beginning of the end of rugby as we know it.

On the face of it, the omens are promising.The world sevens circuit has proved the key to the Olympics and the Olympics could prove the key to the mass markets that have so far remained stubbornly out of rugby's reach.

At the same time as more and more broadcasters and sports administrators woke up to the entertainment value of sevens tournaments, more and more of the lesser nations woke up to the fact that, in the abbreviated form of the game at least, they might have a chance of success against the traditional rugby powerhouses.

In an equally happy coincidence, more and more sportswomen saw rugby as a suitable vehicle for their athletic ambitions and the combination helped rugby present an unanswerable case to the IOC, which had long been looking for a sport capable of packing out the athletics stadium during the early part of the Games.

Olympic recognition removes all sorts of stumbling blocks. Many governments will only fund Olympic sports.

Others, like Russia, only allow their educational establishments to teach sports that feature in the Games. All of them, so the theory goes, will be attracted by the lure of Olympic medals and all of them will believe that, given the example already set by Fiji, Kenya and the like, they will have a realistic chance of achieving them.

Millions of pounds are expected to be thrown in rugby's direction and billions expected to take up the sport.

Brazil, now confirmed as hosts to the 2016 Games, and already starting to make waves in women's sevens, has a population of 190 million.

India's population is 1.1 billion, China's 1.3 billion. Were the Chinese army to adopt rugby as part of its physical fitness regime – and reportedly they are keen to do so because of the discipline and teamwork involved – China would, at a stroke, have the largest playing union in the world.

But the chances are that the new rugby nations will have only a passing interest in the longer form of the game. Sevens is where the medals can be found, and sevens is relatively easy to coach and organise.

There's every likelihood that the new kids on the block, and possibly some of the older nations as well, might choose to focus all their resources on sevens success. New audiences find sevens easier on the eye, easier to understand, and requiring a much shorter attention span.

There's every possibility that sevens, like its Twenty20 counterpart in cricket, will start to attract greater interest, larger crowds and obscenely large sums of money. There's every likelihood too, that the Olympics will come to dominate a rugby calendar that, in international terms at least, has come to be defined by World Cups and Lions tours.

Top players may, at the moment be convinced that they can't play both forms of the game at international level.

There isn't the time, or to be fair, the incentive. Sevens is seen as a specialist, albeit increasingly glamorous, option at the margins in terms of public interest and media coverage.

The fifteen-a-side version is seen as the senior service, the true test of a player, the stage on which reputations – and big money – are made. The chance of taking part in an Olympics may well change their thinking.

But, does it matter? In one sense, the traditional vision of rugby could hardly be more vulnerable. Its reputation has been tarnished by a succession of scandals off the field, while – for a host of well-aired reasons including new laws, better defences and negative coaches – its value as a spectacle has decreased dramatically.

The return of rugby to the Olympics should create a whole new audience and recruit millions of new players, but it may also – rather as cricket has done with Twenty20 – create a monster which will change both the public face of the sport and challenge the traditional hierarchies within it.

For the rugby we know and love, this could be the best of timing or the worst of timing.