Niall Harbison argues that Twitter isn't particularly effective at driving traffic to journalistic enterprises - and that it's diminishing the need for some professional reporting:

Last week in Ireland somebody drove a cement truck in to the main government buildings as an act of protest against the people who run the country. Although fairly tame the attack did draw the attention of the country for the day and got picked up all over the mainstream press on radio, TV and print. The problem for the media though is that even though they were all on Twitter the story was pretty much dead by the time they got it.

A simple photo taken by @davidmaybury and posted to Twitter was all I needed to see to understand the story.

I didn’t need to see it on the cover of the Irish Times, I didn’t need to tune in to the TV to see photos of the truck being towed away nor did I need to buy the paper the next day for analysis. One simple picture posted on Twitter and delivered by my own network on Twitter spoke a thousand words and marginalized the entire press in terms of delivering news to me. There is no doubt that we will always need to get more in depth analysis from the press but to a large extend some of their lunch is being eaten by punters in the street and Twitter means they are losing more and more control over how a story breaks. If you work in the industry and that control is taken away that has to be a very scary thing.

But long experience proves media consumers are attracted to stories that they've already learned about elsewhere. Once people heard Princess Diana died in a car crash, there wasn't any need to buy the issue that People rushed to press. That didn't stop multitudes from snapping it up in the supermarket checkout aisle. The press, treated as a single entity, produces all sorts of redundant, useless information.

In aggregate, the audience proves daily willing to consume it.

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