Oh, for the certainties of yesteryear. There was a time when it was clear where you stood in the film festival world. Everyone knew their place and God was in his heaven, or at least in an arthouse cinema.

The year was more or less happily divided between well-known events with the established auteurs at one end, and the wannabe auteurs and experimental types at the other. Then the brash international market gatecrashed the garden party and now all the talk is of market 'positioning'.

If the P word isn't objectionable enough in itself, by the time you've worked out what the hell your position is, you find some upstart is trying to muscle in.

This week demonstrates the point. Rotterdam and Sundance occupy, broadly speaking, the same space as finders of new talent. They compete in a roundabout way with each other for the attention of the industry and with a host of emerging events for talent.

Each built its reputation as a finder of new film-makers but - now everyone is claiming the same raison d'etre - 'we're the festival of discovery' has become the worst chat-up line in the industry.

The jobs of festival heads and programmers are getting harder every year, to which the industry's response should be 'good'.

Still, there's genuine confusion out there: knowing how to successfully navigate a more complex calendar is a challenge that many could live without. Given the tightening of belts that is likely for many companies this year, not being sure of travel plans is even more of a headache. The inconvenience of choice is the quintessential postmodern complaint.

It's also true that not every competition is healthy. The fight for celebrity guests is one of the less attractive aspect of festivals in recent years and the benefits are far from certain. A flash of A-list flesh may get some instant attention but it soon melts away into the Sunday supplements before the films unspool.

But what matters is the business of film. Lose the interest of the industry - which, after all, decides what makes it into the public consciousness - and you lose your credibility.

So festivals and markets are now constantly on their toes and eager to woo buyers and sellers. So they should be.

At Sundance last year, some $45m is reported to have changed hands. That could be topped this year - though perhaps not at the inflated prices of recent years. The writers' strike may help by putting a premium on completed projects.

For Rotterdam, keeping the business flowing is more of a challenge, squeezed as it is between the expanding Sundance and Berlin. Reinvention for such events is a fact of life and Rotterdam CineMart manager Marit van den Elshout is surely right to say the best way to celebrate a 25-year history is to get on with the future.

It may not always feel that way, but the current market shake-up is a sign of success not failure. The ongoing fight in the US between Netflix and Apple, both of which have announced significant movie download plans, is a reminder that digital distribution will create further demand for film.

Today's fragmentation is only a sign of adapting to the realities of tomorrow's markets. The role of festivals in finding workable gems among a growing amount of product will be critical - the industry is less interested in how long the tail is and more about how fat the belly might be.

A few new entrants will, as Sundance has done since 1978, find themselves a slot in the industry year and most, though probably not all, established festivals will adapt and survive.

However much we may yearn for past certainties, the film business has, and always will, thrive on perpetual motion.