In the last rotation of the Microsoft Certified Masters for SQL Server 2008, I had the pleasure of having Jimmy May in the class. One topic we covered was on disk partition alignment and as I knew Jimmy had been working on the whitepaper, I got him to talk to the class on that topic.
The whitepaper is finally out and I note that another SQL friend Denny Lee is the co-author. You can download it here: http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=5b343389-f7c9-43d0-9892-ddcf55890529