Microsoft has been putting several of the dev team blogs onto the list of the SQL Server blogs reported by the Microsoft Communities page. The Communities page in the SQL Server TechCenter links to this list.
Plus, Conor Cunningham, PM for the SQL Server Query Optimizer Team, has announced a new blog site for the team at:
They're going to try to publish best practices, tips, tricks, and whatever else comes to mind. I'm also happy to pass along suggestions for topics or you can do it yourself via their site.