By Martin Rosenbaum
BBC News political programmes
Four years in the waiting, the Freedom of Information Act has finally come into full force. But will it really change the way journalists find stories and let the public know what is really going on?
Two years ago I visited the Prime Minister's office.
The friendly staff were welcoming to me and Michael Crick, the reporter I was with, and gave us a large pile of Mr Blair's correspondence with other world leaders, which we sat down and read.
But we weren't in Downing Street - we were in Stockholm in the office of the Swedish Prime Minister, Goran Persson.
Sweden has possibly the strongest freedom of information laws in the world, and the government there is happy to make available the sort of documents that other countries like Britain have preferred to keep secret.
The pile of Mr Blair's letters to Mr Persson contained one we found particularly enjoyable. It was sent in the wake of England beating Germany 5-1 in the World Cup qualifiers in 2001, a triumph for the new England manager Sven-Goran Eriksson.
Mr Persson was interviewed on BBC Radio 4's Today programme about this boost to Anglo-Swedish relations - following which Tony Blair dispatched him a short handwritten note:
"You are a star," said Mr Blair. "You can appear on British radio anytime. And thank you for Sven."
But when we asked Downing Street for copies of Tony Blair's letters to Goran Persson, we were told they could not release them as it might "damage our international relations".
Who was the person who told us this? The Cabinet Office official with the grand title of 'openness co-ordinator'.
Questions being asked
The question journalists are asking themselves now is how will this traditional British tendency to official secrecy change with the Freedom of Information Act ('Foia' in the jargon) in force from 1 January?
That is a critical issue for the public too because it determines what they will ultimately know or not know.
The media will be some of the most enthusiastic users of the powerful new rights to government information which the Act lays down.
In some cases how much is revealed will still depend on the attitude of civil servants.
Would Mr Blair's international writings on the England football manager now become public?
That will be determined by whether officials think it is more in the public interest to reveal them or to avoid prejudice to our international relations by keeping
But whatever their inclinations there will be many situations where public authorities will now be forced to reveal documents on request.
This will give British journalists the sort of tool that their colleagues elsewhere have made extensive use of for years.
Journalists hope to use FOI to open more doors
Freedom of information legislation helped the Washington Post report the role played by US Defense Secretary Donald Rumsfeld in assisting Saddam Hussein in the 1980s.
It led to the Irish Times revealing the spiralling costs of a proposed new national stadium in Ireland, resulting in the plan being abandoned.
And it enabled a Swedish newspaper to expose how top army officers were regularly breaking the rules on using official vehicles for private journeys.
Sometimes Foia will lead to scoops. Sometimes it will just lead to journalists having more background information.
The time delays involved in getting requests dealt with will make it of less use for routine, daily news reporting. But it should be invaluable for longer-term investigations and research.
Corridors of power
If we had already had freedom of information in Britain, who knows how better informed journalism here would have been on topics like the outbreak of foot-and-mouth disease, Gulf War syndrome, the hospital 'superbug' MRSA or even visas for Filipino nannies.
Perhaps we will find out, if journalists decide to revisit some of these stories in search of information which they found it difficult to obtain at the time.
And plenty of journalists will certainly be using the Act to try to find out more about the process leading to the Iraq War, particularly the vexed issue of the Attorney-General's legal advice on the legality of the conflict.
But it's not only big national issues which Foia will affect. Since it covers some 100,000 public bodies down to local councils, police forces, primary schools and GP surgeries, it could be that it will be the local media which will get the most out of it.
And in the spirit of freedom of information, here's a little advance tip-off for the openness co-ordinator in the Cabinet Office
I'm going to be putting in a request for Tony Blair's recent letters to Goran Persson.