It's a sad fact that many journalists who have been scooped or cut out of a breaking news story react by knocking it down. "That's old news," they say, "we knew that already." Sometimes it's true. But mostly it's sour grapes.

And the reaction by many US media outlets to the latest US embassy cables disclosures – as rich a source of commentary on contemporary US foreign policy as we're ever likely to have in one cache – has been much the same.

Policy wonk Peter Beinart summed up what he knew of the cables as: "Valuable insights – if you've been living under a rock all century." The "latest WikiLeaks dump," he announced, "is to American foreign policy what the Starr report was to presidential politics – fun, in a voyeuristic sort of way, revealing, but not about important things, and ultimately, more trouble than it is worth".

Blogger Andrew Sullivan quoted Beinart approvingly. Admitting "I have not yet plumbed the depths of all these documents," Sullivan pronounced: "I guess to the member of the American public who has better things to do than analyse foreign policy, it may indeed seem news that Saudi Arabia wants war. But to anyone else: meh."

Beinart and Sullivan weren't alone by any means. Foreign Policy – a magazine that one would expect to be in heaven with the detail the cables provide – published a knocking piece all the way from Moscow that derided the disclosures as banal "document vomit".

There are two problems here. One is the shrug of the shoulder (or "meh") from the likes of Beinart, Sullivan and FP is just the "that's old news" dodge revisited. This world-weary posture turns everything into "old news", of course, since there's nothing new under the sun by that argument.

To be fair, the bigger problem for WikiSceptics is that they made their "nothing to see here, move along" pronouncements on Monday, when just a few of the 250,000 cables had been revealed. With each passing day more and more details emerge, about every corner of the globe, and will do for weeks if not months.

But as new facts emerge people, are entitled to change their minds – as Foreign Policy did, launching its own dedicated WikiLeaks blog to cope with the news being generated by the "document vomit". By Tuesday Sullivan was enthusiastically describing them as the "WikiLeaks revelations" rather than "meh". (The Daily Beast had already undercut Beinart by running alongside his words a link headlined: "The 9 Most Shocking WikiLeaks Secrets".)

So what have we learned from the documents? Here's an incomplete list – incomplete because there are tens of thousands of cables still out there.

Yes, we may have known that these two men were close – but this is the first time allegations of financial ties have surfaced, with Putin allegedly giving Berlusconi a cut of energy contracts.

The extraordinary tale of how the Bush administration threatened Spain to leave off its prosecutions over the US's use of torture – and how senior Spanish legal officials connived with the US to help them.

The shocking news that the US state department, acting on a wishlist drawn up by the CIA, asked its diplomats to obtain credit card accounts, email addresses, mobile phone numbers and even the DNA of UN officials, a possible breach of international law.

Even knowing that there was widespread corruption is no preparation for the magnitude of it, suggesting the US has a hopeless task in Afghanistan.

A hugely damaging revelation in Argentina, straining relations with the US after the cables revealed an official request to find out if the country's president was on "medication" and how she dealt with stress.

Mervyn King faced calls for his resignation and a very uncomfortable position after he was revealed to be advising the Conservatives on fiscal policy while denigrating them in secret to US diplomats.

7. The British government remains in thrall to the US

Over Diego Garcia, over an international cluster munitions ban, over using British bases for rendition and spying flights, the British authorities were either ignored, manipulated or co-opted.

And that's not even a particularly complete list of what we know, because there has been so much it's very difficult to decide what has had the most impact. But this is all far from over. For all we know there is a ticking time bomb sitting among the unpublished cables – unnoticed by the teams of journalists working through them – waiting to go off.