Technical Communities Portal and finding Microsoft blogs
If you are looking for blogs by Microsoft Employees on specific topics then a good place to start is the Microsoft Technical Communities portal. This portal is an entry point for Blogs, chats, newsgroups and webcasts. If you click the link for blogs you can then search for blogs by category and keyword. For example, here are the search results for the "Debugging" category.
Having a blog listed there requires the Microsoftie to register their blog in an internal tool and specify the various categories which apply. I thought I had registered mine some time ago which but I recently learned it not was showing up as my colleague Carlo brought to my attention. Turns out I had accidentally somehow registered my blog as being in Estonian (comes after 'English' in the alphabet)!