Al Qaeda, chief Ayman al Zawahiri, recently confirmed in a video recording the death of Abu Yahya al Libi, a senior al Qaeda commander (chief of combat operations) during a June 4th American UAV attack in Pakistan's North Waziristan. Al Libi was widely considered to be al Qaeda's number two man.
After the June 4th attack, for the rest of the month the chatter in and around North Waziristan (a terrorist sanctuary maintained by the Pakistani military) was that al Libi was indeed dead. However, senior terrorists claimed al Libi was not in the car hit with the missile. Then a video appeared featuring al Libi but nothing was said in that video indicating when it was made.
All this is nothing unusual for al Qaeda. The organization is constantly losing key people but has learned to be careful passing such information around internal channels, as the Americans seek to track the flow of such communications to set up attacks on other terrorist leaders. So al Qaeda takes its time, often using couriers to personally deliver messages between senior leaders about what happened to whom and what to do next. Sometimes al Qaeda prefers to deny they lost a guy for a while, and then admit he is dead but from other causes. Other reasons for delays are to line up a suitable replacement and make sure the new guy is safe before letting the world know he's just become a more prominent target. Lastly, al Qaeda likes to honor their dead and the senior dead guys require a suitable eulogy and fulsome praise from other prominent mass murderers. This takes time to prepare. In al Libis case it took three months.