Rule No 8 on one internet guide to the etiquette of tweeting is that What's Rude in Life is Rude on Twitter. The film director Michael Winner appears not to have read it. Perhaps the first seven were so riveting he never got that far. At any rate he has caused something of a stir in the world of social networking decorum by engaging in a day long off-on discussion with his Twitter followers about the physical appearance of the poker-playing TV presenter Victoria Coren. Ms Coren was so incensed she found his phone number and rang him to complain. Mr Winner responded by tweeting that it is very rude to ring people you do not know at 10.25pm.

There are clearly some interesting cultural clashes here as to what goes where in the hierarchy of rudeness. The pair have been appealing to others on Twitter to support their respective priorities. Whether the wisdom of crowds has much to offer here is debatable. 'Who is Victoria Coren, and why are her breasts news?' one tweeter asked. He clearly needs to get out more. But then perhaps that is true of many Twitter addicts for whom the phenomenon blurs the lines between reality and fantasy, public and private. There is a world elsewhere. But whether we occupy that, or remain in the ether, it is as well to remember that everywhere Rule No 8 applies.