The fact that the title of the August 6 PDB was "Bin Laden determined to attack inside the United States" will probably garner the headlines, but I think the more significant disclosure came from a comment by Bob Kerrey.
"In the spirit of further declassification, this is what the August 6th memo said to the president: that the FBI indicates patterns of suspicious activity in the United States consistent with preparations for hijacking."
Transcript of Rice Testimony
This seems to rebut not only Rice's argument that the August 6 memo was merely "a historical document" that did not contain warnings, but the specific reference to suspicious activity in preparation for hijacking is chilling. I'm not sure why no one in the post testimony coverage is following up on this.