User blog comment:Trellar/Updates to Log In and Sign Up/@comment-8072-20120302003402/@comment-4068340-20120302005100

As stated in the post, a confirmed email address is only required for new users signing up. We found that often times when people wrote in to Special:Contact seeking help and advice, they were unable to receive a response from us, due to the fact that their email address is incorrect. In addition, sometimes we run contests and special events on wikis. For example, we would use your email address as a way to discreetly contact you if you won. We'd hate for you not to hear about something awesome (such as winning the grand prize for the WoW Wiki Contest!), which is why we're now making it a requirement. I hope you understand our reasoning behind it.