Research published today by search marketing consultancy Tamar has concluded that most of the major personal finance firms have failed to set up an official presence on sites such as Facebook, while customers were discussing their brands and their customer service on unofficial groups.
The Social Media Sectors Report analysed 10 top brands from each of the travel, retail and financial services sectors and their positive and negative presence in groups on Facebook, Myspace and Bebo.
It found that only 30% of the major financial brands had a social media presence, while 80% of them were being discussed by customers in unofficial groups on the sites.
The growth of social networking has seen the growth of "customer revenge" groups. When Egg announced earlier this year that it was cancelling the credit cards of 161,000 customers, dozens of customers joined unofficial groups on Facebook to express their anger at the move.
Tamar has argued that the rise in internet protest groups, with names such as "Egg and Citigroup can shove their credit cards up their arses", needs to be taken seriously by companies.
Henry Elliss, the head of social media at the search agency, said: "A poor official presence will do nothing to help this."
HSBC has also incurred the wrath of Facebook users in recent months, after it announced changes to the interest-free overdraft on its graduate account. One group on the site, entitled Stop the Great HSBC Graduate Rip-Off, now has 4,600 members.
But the report found that unofficial groups on social networking sites were not limited to negative comments about a brand.
For example, one group related to Egg is entitled "The Guinea Pig Adverts Give My Life New Meaning" and has 145 members.
The newly published research has also singled out travel firms for failing to capitalise on the number of people who use social networking sites to discuss their holiday experiences.
In contrast, the retail sector was praised for building up a strong presence online.
Elliss said: "More vociferous consumers are using social media as a platform to highlight positive experience, not just the negative.
"Failure by brands to engage with groups set up by consumers could see opportunities to engage with customers slip by."
Tamar, whose clients include Lloyds TSB, Natwest and the Post Office, has urged social networking sites to make a clearer differentiation between officially-endorsed brand pages on the site and unofficial groups set up by fans or disgruntled customers.