Hill & Knowlton's Tech Decision-makers Study indicates online media are key to influencing decision-makers about which technology services and hardware they should be buying for their businesses.

But observers warned that while social networking is an important tool, it brings unique challenges. Ivan Ristic, director of digital PR agency Diffusion, said it was vital that technology vendors 'put in place effective online monitoring to understand what is being said about their products, act rapidly to correct inaccuracies and proactively encourage blogger advocacy'.

The survey did show, however, that social media had limited impact in certain areas. For example, in terms of reputation, online information is significantly less influential.

Of the 400 decision-makers surveyed in the UK, Canada and the US, 67 per cent saw industry analyst reports as having a strong impact on their perceptions of a technology company, whereas only 47 and 48 per cent saw online sources and industry blogs as influential.

The survey illustrates the value of different comms strategies, but suggests PR firms should carefully target their campaigns.