Wikinews was just one of many news sites that reported record traffic following the bombings, recording an eightfold increase on 7 July.
The project was launched in December 2004 as an offshoot of Wikipedia, an online encyclopedia that invites anyone to add or edit information. Since Wikipedia was established in January 2001, more than 1.3 million articles have been written by its international users.
Though Wikinews is still much smaller than Wikipedia it is built on the same model, relying on amateur journalists and editors around the world to contribute and edit news stories as they happen.
Wikipedia has consistently seen significant peaks in traffic following major news events including 9/11 and the Space Shuttle Columbia disaster, but this event was the first time that Wikinews itself had attracted a significant audience.
"The level of interest in Wikinews this time was unprecedented," said Erik Moeller, Wikipedia developer and journalist.
"What was new in this case was the massive surge of traffic to the major Wikinews language editions and, for the first time since its launch, Wikinews itself was referenced in a large number of blogs."
Wikipedia vs Wikinews
The structure of information on the two sites is quite different; Wikipedia is designed to be a source of information and reference, whereas Wikinews is a news provider.
Wikipedia's record of the event is an impressive, detailed account of the bombings that has been regularly revised and updated as new information has been made public. The listing now includes a timeline of events, lists of casualties and suspects, emergency contacts details and the Red Cross relief fund and coverage of the response from the media and financial markets.
Wikipedia has a policy that it will only publish information already reported by a reliable source - a safety net designed to make sure that content is accurate. The first report on the bombings was filed by one user at 10:18 GMT on 7 July - just an hour and a half after the first explosion - but in line with this policy she waited for confirmation in the mainstream media before publishing it.
Wikinews, on the other hand, was founded specifically to encourage original reporting. The first story on the bombings was posted at 9:28 GMT - little more than 30 minutes after the first blast. A further 23 stories were contributed in the following six days, eight of which claimed to include at least some original reporting; first-hand eyewitness accounts, information from officials or photos from the scene.
Wikinews is only seven months old and its strategy for dealing with breaking news is still evolving. Among other developments are redesign plans that will allow casual readers to scan summaries of stories more easily. All aspects of the site are debated, developed, reviewed and built by its users and a hardcore of contributors who are highly ambitious and competitive in helping the site progress.
"We want to be the best - to beat the establishment to deliver the best quality with no bias," said user CGorman, reviewing the site's coverage of the London bombings.
Mr Moeller believes Wikinews is likely to experience similar problems as Wikipedia as the project develops.
"Traditional encyclopedias are not cooperating with us and I think Wikinews will be treated as competition in a similar way," he said.
"We will soon hear accusations that we are 'stealing' news content, but I do see some hope for collaboration with publicly funded news organisations."
Trusting 'free' news
As for the accuracy and reliability of Wikinews coverage, Mr Moeller said the site should be trusted as much - or as little - as any other news provider.
"Media consumers should generally be critical and observant, whether they're using Time Warner-controlled media, News Corporation-controlled media or people-controlled media," he told journalism.co.uk.
Emphasis is on the responsibility of individual writers to verify their sources, and users build their own reputation within the Wikinews community.
Wikinews writers - or 'Wikinewsies' - write for free and their motivation is varied.
"Many Wikinewsies are news addicts, and writing stories is a way for them to simultaneously feed their addiction and feel useful doing it," said Mr Moeller.
"Others want to pick those stories of the day that they consider socially important and promote them in this way."
Other contributors write about their own communities and use Wikinews to record their experiences and for events such as the London bombings, writing can be cathartic and a way for users to feel they are contributing to something useful and constructive.
News readers want to be news writers
Analysis of the Wikinews and Wikipedia audiences shows that those interested in reading news appear to be more likely to contribute to it - a healthy indicator for the future of the news project.
English-language Wikipedia has 75 times the audience of English Wikinews, but only five times the number of editors.
Wikipedia records an average 1.5 million visits per day against Wikinews's 20,000.
By 9PM on 11 July, the Wikipedia entry on the London bombings had been edited 3973 times by 1083 users. The first Wikinews article on the attacks was edited by 615 times by 215 users.
This record number of edits did cause some problems. Multiple users were editing the same page at once, which meant edited pages were constantly overwritten. There were also some problems with vandalism, and 16 users were blocked from the site as a result.
"While Wikinews is still much, much smaller than Wikipedia, the potential for news coverage goes far beyond what Wikipedia is currently doing," said Mr Moeller.
"If Wikinews grows to the scale of today's Wikipedia, imagine the potential coverage for an event of this type."
Acquiring reader trust
Simon Waldman, director of digital publishing at Guardian Unlimited, feels that the Wikipedia publishing model doesn't comfortably transfer to Wikinews.
"What Wikipedia does is desperately impressive. It is effectively building an instant record of history in response to breaking news and that is truly new," he told journalism.co.uk.
"It wants to build on the Wikipedia model of using external sources to make sure everything is accurate. But that means it can't support original reporting because it can't verify that information - so writers just end up copying stories from the wire."
Wikipedia's success is down to its complex social structure and that has taken several years to develop and prove, he said.
"Everything on the internet is about acquired trust, and news sites earn their spurs with each news story," said Mr Waldman.
"A news site has two jobs; one to deliver the story accurately and as quickly as possible, and two to make sure that your site stays up. If you're doing that, everything else will slot into place."
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