Huge numbers of disappointed Commonwealth Bank (ASX: CBA) customers have taken to the Internet to vent their outrage over the 'unfair' variable interest rate hike of 0.45 per cent this week.

Online and social media tracking company, Cyber Chatter has analysed more than 2700 online conversations about the Commonwealth Bank, showing a massive increase in negative sentiment towards the organisation across blogs, forums, microblogs and social networking sites.

Negative online conversations about the big bank spiked on Tuesday to 10 times the average number, with 801 online posts published, blasting the company over its interest rate rise.

The results showed negative opinions of the bank far outweighed the positive online and the majority of the outcry was unleashed on microblogging sites like Twitter.

The tracking showed men were most angered, with 89 per cent of negative online conversations about the bank led by males, compared to only 11 per cent for females.

Yesterday, Australian Prime Minister Julia Gillard joined the fray in publicly criticising the country's banks for imposing higher rates above that of the Reserve Bank.

"I'm angry and I understand why Australians paying mortgages are angry," Gillard told commercial television Thursday as she urged unhappy customers to switch lenders.

So far, among the four major banks in Australia, the Commonwealth Bank is the only one that has jacked up rates by 0.45 percentage points immediately after the RBA's announcement of its 0.25 point increase. The National Australia Bank, Westpac Banking Corp. and the Australia and New Zealand Banking Corp. have all deferred their rate adjustments amidst the public furor.