As more and more browser developers add the support for the Do Not Track header to their products, and since Microsoft's decision of making IE10 have the Do Not Track on by default, the discussion about whether websites should or should not accept this particular user request has reached a new level.

Microsoft's forceful step has already been criticized by the Apache Foundation, which added a patch to its open source Apache HTTP Server that will make it ignore the DNT header if sent by the IE10 browser.

"The only reason DNT exists is to express a non-default option. That's all it does. It does not protect anyone's privacy unless the recipients believe it was set by a real human being, with a real preference for privacy over personalization," explained the Roy Fielding, the creator of the patch and one of the founders of the Apache HTTP Server Project, but also a scientist at Adobe and one of the editors of the DNT standard.

Apache has since thawed a bit on that stance and has offered the code for ignoring DNT as an option in the Server's configuration files, but now Yahoo! has made it clear that it will also disregard the DNT signal from IE 10.

"Recently, Microsoft unilaterally decided to turn on DNT in Internet Explorer 10 by default, rather than at users’ direction. In our view, this degrades the experience for the majority of users and makes it hard to deliver on our value proposition to them. It basically means that the DNT signal from IE10 doesn’t express user intent," the company pointed out in a post on its Policy Blog.

"Ultimately, we believe that DNT must map to user intent — not to the intent of one browser creator, plug-in writer, or third-party software service," they explained their decision, adding that users can use the company's Ad Interest Manager tool in order to have more control over personalized advertising on Yahoo!.

But Sophos' Chester Wisniewski thinks that their argument is invalid, especially because "the DNT setting is clearly and explicitly stated during installation and is a clear expression of the user's choice to not be tracked."

Yahoo! should definitely be able to track the users who have logged into their services and expect personalized content, he says, but if someone who has not logged in lands on some of their assets, they should respect the DNT request and show them random ads.