The importance to firms of Web 2.0 strategies such as deeper customer engagement was again highlighted this week by new research which found some major brands are suffering because they aren't generating positive online word-of-mouth.

The biannual Advocacy Index, conducted by PR firm Kaizo, looked at the impact of online word of mouth on twenty brands in four different sectors by measuring positive and negative comments on Google.com, Google News, Google Groups and Google Blogs.

Symbian won the software category with 30 per cent, while Microsoft came bottom with -32.5. other big names which scored low due to a large amount of negative comments were Symantec with -15 and Oracle with -18.

“The results of our analysis of the software sector show that personal recommendations – both positive and negative – hold more power than any other kind of marketing influence," said Kaizo managing director Rhodri Harries. " Organisations [should] ensure that their communications strategy embraces all the sources of information online – particularly those created by users."