I've really enjoyed the much greater openness that the SQL Server development team has been exhibiting since late in the development of SQL Server 2005. Since thing dev team "glastnost" has expanded to include many of the individual subteams within the larger 1000 person development team.
Two really good resources that I've added to my blog roll include:
1. The SQL Server Storage Team blog
2. The SQL Server Customer Advisory Team blog
If you haven't already added them, let me tell you that you are missing out!
Another website that's recently gained my attention is BAARF. No, it's not some sophomoric humor website dedicated to over the top beer swilling college students and what happens when they overindulge - though it you know of any, I'd like to hear about them. BAARF is an acronym for "Battle Against All RAID Five". (Of course, the full name sounds a lot like a poorly translated title for a Japanese movie - but I digress.) It's a website that's chalked full of great tips and information about tuning IO and RAID subsystems.
Check them out! Oh, and give me a holler if you have any other good leads.