This interview is a bit old, but NarG talks about the I/O manager and the driver model.  If you ever wanted some inside depth on how the I/O manager works, this one is for you.   NarG is the lead for all of WDF (UMDF, KMDF, SDV, PFD) and he certainly knows his stuff ;). 

Paul (who wrote previously on my blog about work items and thread agnostic I/O) also has an interview on I/O cancelation and new Vista features which is also a good listen.