The original memo text can be found here. Read the whole thing, but these are the most significant lines from the non-historical part of the memo:

We have not been able to corroborate some of the more sensational threat reporting, such as that from a ---- service in 1998 saying that Bin Laden wanted to hijack a U.S. aircraft to gain the release of "Blind Sheikh" Omar Abdel Rahman and other U.S.-held extremists.

Nevertheless, FBI information since that time indicates patterns of suspicious activity in this country consistent with preparations for hijackings or other types of attacks, including recent surveillance of federal buildings in New York.

Now, some quotes specifically discussing this memo from a recent New York Times article:

...While some of the intelligence went back years, other warnings — including one that Al Qaeda seemed interested in hijacking a plane inside this country — had been delivered to the president on Aug. 6, 2001, just a month before the attacks.

...The most striking came in the Aug. 6 memorandum presented in an intelligence briefing the White House says Mr. Bush requested. Titled "Bin Laden Determined to Strike in U.S.," the memorandum was declassified this month under pressure from the commission. After referring to a British tip in 1998 that Islamic fundamentalists wanted to hijack a plane, it went on to warn: "Nevertheless, F.B.I. information since that time indicates patterns of suspicious activity in this country consistent with preparations for hijackings or other types of attacks." Mr. Bush has said the briefing did not provide specific details of when and where an attack might take place.

...In August, C.I.A. officials prepared a briefing about the possibility of Qaeda operations inside the United States, including the use of aircraft in terror attacks.

The briefing paper was presented to Mr. Bush on Aug. 6 at his Texas ranch. The memorandum, declassified on April 10 by the White House at the commission's request, included some ominous information. It said that Qaeda operatives had been in the United States for years, might be planning an attack in the United States and could be focusing on a building in Lower Manhattan as a target.

The warning in the memo described hijacking a plane to take hostages for ransom, not to fly into buildings. This critical detail is omitted from the NYT article.

The memo mentions "surveillance of federal buildings in New York." Nowhere is anything said about "a building in Lower Manhattan." The word "Manhattan" does not even appear in the memo, and this is a complete invention of the article.

The NYT omits and alters information in the memo to continue the impression that the memo was a dire warning of airplane attacks on buildings. That they do so even while the actual memo text is open to the public doesn't speak highly of their opinion of the American citizen.

I wish I had the text for all the memos discussed in this article. I would bet they, too, would say something very different than the impressions that the media are trying to give.