On 18 April The Guardian printed an extract from Downing Street's Twitter feed on its front page, showing all PROs and marketers that social media have become an integral part of Labour's comms strategy.
For those that do not know, Twitter is a social networking tool that allows users to send updates or 'tweets' to the website. Updates are automatically delivered to other 'Twitterers' who have signed up to receive them.
Downing Street provides marketers with a good example of how to engage with social media, particularly Twitter. Using it to document Brown's trip to the US, the '@DowningStreet' Twitter ID sends regular updates. More importantly, it also replies to tweets from its followers.
The fact that Brown's team is responding to tweets as they come in shows that even the most public of 'corporations' can harness the benefits of social media.
Organisations who have been intimidated by its power (particularly those in government and education) because they are worried about controlling their messages should look to '@DowningStreet' as a positive example of two-way communication.
Twitter is just a small part of Brown's web strategy, which also includes a blog and Flickr, the photo sharing service, mirroring the social media strategy adopted by many of the candidates in the US presidential elections.
So what is the opportunity for PROs? Is it convincing your CEO to 'tweet' instead of blog? Is it running news streams from events or conferences through Twitter? What about communicating with journalists through the site?
I've been following one particular national journalist who tweeted the topic of a story he was working on, which happened to be relevant to one of my clients. The result was national coverage.
Yet, there are still no hard and fast rules on social media as a comms channel - we are constantly learning valuable lessons as we experiment. Using Twitter along with other social media tools is just one of these lessons.
And finally, how did I learn about Twitter being on The Guardian's cover that morning? I was told by my friends on Twitter before I even picked up the paper.
Marc Berry is MD of Spider, the digital offshoot of Loewy-owned agency Mantra.