Damocles got a lot of rest while that sword was suspended over his head, too.
The threat remains.
Libraries are not going to go back to their previous way of doing business merely because Mr. Ashcroft is going to declassify his investigations thus far. It could possibly be that he hasn't used the provision because he realizes that there is now precious little data to collect, on anyone about anything. The only way to collect data will be to collect the computers on which it may or may not be stored, and it's very hard to conceal absent hardware from the public. There goes his secrecy.
As Robert says, if he hasn't used it, why not just repeal it?
Regards--
Mary Anne