"I just prefer reading about this sort of thing other places. Not on HN."
To be fair, this does involve the use of twitter, and other social news sites, and technology in general, to challenge existing legal/PR practices i.e. trying to gag news sites. Furthermore, it may be possible that the twitter-storm made Carter Ruck decide that by sticking to their guns the storm would increase, thereby working against their aim of minimising Trafigura's publicity.
It's a good example of how the internet changes society, providing the internet did play a role in Carter Ruck's decision to cave in, which I would guess is likely.
Carter Ruck were trying to suppress anyone knowing about the report, to such an extent that they tried to stop the Guardian reporting on a parliamentary question that spoke about it. Twitter, fueled from the outrage in regard to gagging the Guardian, started to link to that report extensively.
The longer Carter Ruck decided to persue this course of action, the more Twitter would link to the report. Therefore, it was wise for Carter Ruck to remove Twitter's fuel. It was wise to stop attempting to gag the Guardian. (Attempting to sue all those on Twitter would be unfeasible, and suing Twitter itself would add even more fuel to the fire)
I have no proof this is what Carter Ruck thought. But it's certainly a logical and sensible course of action for Carter Ruck, which makes it likely.
I'm not so sure about Twitter's specific role, but the easy availability of online stories does make a massive difference. If you want to see a much more successful attempt to gag the British press, check out the Spycatcher nonsense:
http://en.wikipedia.org/wiki/Spycatcher
That was 1987, and the main difference was the lack of easy access to foreign controlled media from within the UK made it possible to prevent people reading anything about the allegations in the book. This latest attempt shows that's no longer possible.
HN readers might find that interesting, not only because of the legal ramifications but because SpyCatcher detailed much (not all) of the UK security services' use of public key cryptography, around the same time that PGP was starting to gain traction in the US and the US government attempted to label the algorithm as a 'munition'. Lovers of cloak-and-dagger spycraft were rather disappointed in the book but it's interesting, if dated, for anyone with an interest in strong crypto.
Carter Ruck are a leading British law firm. Their lawyers probably read newspapers. Social media sites are very hot news in the UK, and Twitter is probably the second most famous after Facebook, which is ridiculously famous. Twitter isn't the domain of those who have protracted conversations on social news sites anymore.
Are you kidding? Some corp poisons a whole lot of people, a law firm tries to gag a news organization and thereby rights to free speech and all you can muster is "Meh"?
I don't think the Trafigura part is especially relevant to HN - corporate misdeeds are covered extensively in other news outlets, and are more Business News or Environment News or Legal News. Don't get me wrong, they seem like an unpleasant corporation, but we could fill the front page many times over each day if we posted every such story.
However, the (mis)use to law to attempt a gagging of the press is a censorship issue, and matters of censorship ad information freedom do seem relevant to HN, so I'm glad you posted it even though I've seen this story elsewhere.
I'm sorry if you feel that corporate murder is a boring topic.