Richard Kerr, former Deputy Director of Central Intelligence, and a preparer of PDBs noted in an NPR interview this morning that the PDB is a "continuity document," that many of its items may be prepared a few days in advance of 'publication,' and that many items rise from an analyst's desk and are refined - as opposed to being written by Kerr or his successor. Kerr had prepared PDBs for Presidents Reagan and Bush.

I also call your attention to a valuable item at The National Security Archive (George Washington University), "The President's Daily Brief" By Thomas S. Blanton, Updated April 12, 2004.

The White House Fact Sheet titled "The August 6, 2001 PDB" that was released along with the 6 August PDB section, in a Q&A format.