A typically stern cautionary covering note accompanies the latest multimedia invitation to one of the autumn’s potential Hollywood blockbusters. Under the sub-heading ‘Review Embargo’, the metaphorical finger wags: ‘With your attendance you recognise that you must not publish any reports or reviews in print, TV, radio or online (including Blogging, Forum, Online Chats, Tweeting, Facebook etc) as per the above.’

As the media-savvy crowd, including a number of supposedly influential print and radio critics, are relieved of their cellphones under threat of expulsion ahead of being given a body search by dark-suited heavies for other possibly secreted recording devices, it’s clear that if piracy is the number one crime against today’s cinema, then a close-run second seems to be reviewing a film at a time not of the distributor’s own choosing.

The delicious irony hovering over the early evening brouhaha— which will be repeated almost once a week in West End cinema lobbies until all the season’s most eagerly anticipated films are in the public arena—is that this particular night’s offering is The Social Network, about the invention of, yes, Facebook, now, arguably, the most potent new democracy of cultural opinion with half a billion subscribers globally.

Blogging? Tweeting? Facebook? So, just who are the film critics now? You, me, everyone might be at least an answer. Long before social networking sites were even the merest twinkle in the eye of cybernauts and wannabe opinion makers, it was all so much simpler. For perhaps the first eight or so decades of film—since the first recorded review noted, on June 15 1896 of May Irwin Kiss, ‘absolutely disgusting’— criticism principally resided with newspaper and magazine contributors as well as the occasional television commentator notably, in this country, Barry Norman, followed, latterly, by Jonathan Ross.

For years, print had it very much its own way with a succession of, in this country at least, fine and eminently quotable critics ranging from legends like Graham Greene, Richard Winnington, Dilys Powell and Alexander Walker to the top of the contemporary crop such as Philip French, Derek Malcolm, Christopher Tookey and Peter Bradshaw.

The first hints, however, that there might be a shift in the potency of opinion from the conventional arenas to the burgeoning world of online probably came in 1999 with the release of a film that cost around $25,000 to shoot. The Blair Witch Project, a spooky thriller craftily packaged as ‘reality footage’, eventually grossed nearly a quarter of a billion dollars around the world following a groundbreaking marketing campaign on the Internet. By the time the film actually hit cinemas, it had become virtually critic-proof.

Ten years later, an article appeared in a reputable if rather obscure European magazine for cineastes. It was headlined starkly The End-of-the- Film-Criticism Industry and in it the veteran critic Jonathan Rosenbaum wrote: ‘One reason why film reviewing… appears to be undergoing a loss of prestige is the rapid growth and expansion of Internet film reviewing and blogging, which has intensified the already popular idea that anyone can be a film critic (unlike, say, a dance critic or a sports commentator— two other professions in which some background knowledge is regarded as essential).’