[nwctwx]

From Feb 2004 (more have been added since: this quotes as 5 of 10):

Al-Zawahri statements often precede attacks

Ayman al-Zawahri, the al-Qaida second-in-command whose voice was heard on audiotapes broadcast this week on Arab television, has made 10 similar public statements in the past six years, five of which were followed within three weeks by deadly terrorist attacks, an NBC News analysis shows.

In two cases, the attacks came within three days of the broadcast of audiotapes or videotapes attributed to al-Zawahri. In both those instances, more than 200 people were killed.

U.S. intelligence officials, who spoke with NBC News on condition of anonymity, said they cannot definitively link al-Zawahri’s statements to the subsequent attacks. But they said that U.S. security officials take seriously any such pronouncements by Osama bin Laden’s right-hand man and study them for any possible “go signals” they might contain instructing al-Qaida operatives to carry out terrorist attacks.

http://msnbc.msn.com/id/4358624/

[nwctwx]

This should have been bold:

In two cases, the attacks came within three days of the broadcast of audiotapes or videotapes attributed to al-Zawahri. In both those instances, more than 200 people were killed.

[Oorang]

I was just getting ready to post the same article. Great minds and all that :-)