Microsoft has started a Microsoft Employee Whitehat hacker blog.
"Welcome to a new blog from Microsoft. The focus of this blog is likely to be a little different from most other blogs you'll see on blogs.msdn.com. Microsoft employs some of the best hackers in the world and actively recruits them and develops them. They work on all kinds of projects, whether it be in development, research, testing, management and of course security. Of course, there is controversy even in the word "hacker" but I don't think that should stop us from using it in the manner I think is the most appropriate."
Paper Link: http://blogs.msdn.com/hackers/