From AP via CTV.ca:

U.S. intelligence analysts have concluded al Qaeda has rebuilt its operating capability to a level not seen since just before the 2001 terrorist attacks, The Associated Press has learned.

The conclusion suggests that the group that launched the most devastating terror attack on the United States has been able to rebuild despite nearly six years of bombings, war and other tactics aimed at crippling it.

Still, numerous government officials say they know of no specific, credible threat of a new attack.

A counterterrorism official familiar with a five-page summary of the new government threat assessment called it a stark appraisal that will be discussed at the White House on Thursday as part of a broader meeting on an upcoming National Intelligence Estimate.

Part of the blame situation seems to be directed to Pakistan. The decision by the government to sign a "peace deal" in North Waziristan last fall is seen as a turning point. (Here's the Beeb's analysis from the time).

U.S. intelligence isn't the only one who's noticed al Qaeda is off the matt. Pakistani journalist Ahmed Rashid wrote a brief article about al Qaeda's comeback in the March 9 Daily Telegraph.