There's another explanation. First, the Taliban use of roadside and suicide bombs has been a failure. The number of people killed per attack is much less than in Iraq. Worse, few foreign troops have been killed. Most of the casualties have been Afghans, which even the Taliban noted has done little for their popularity.
While the bands of Taliban wandering around the south have terrorized many districts in the vicinity of Kandahar (the "capital" of the Taliban), these groups have been unable to escape Coalition (American and NATO) and Afghan troops. U.S. air power is quick to spot the Taliban war parties (100-400 men), trap them and destroy them. So far, at least a third of the Taliban fighters have been killed or captured.
The Taliban have also found that they are not as popular as they thought they were. They also forget that, despite their 300,000 soldiers and troops they had at the end of 2001, the only reliable Taliban enforcers back then was a brigade of several thousand foreign al Qaeda gunmen. The Taliban had to use al Qaeda to keep the population under control because, well, most Afghans were not happy with the Taliban in 2001. Even the Taliban's own army and police were not willing to provide the needed muscle. Somehow the Taliban believe that five years have dulled everyone's memories to the point where the population will welcome the Taliban back. So far, that hasn't happened, but the Taliban believe that, somehow, this will change.
In Afghanistan, the Taliban have called a halt to their Summer Offensive. They pitch this as a "pause" while they wait for people to starve (a drought in the south has halved the wheat harvest there, putting over two million people at risk of starvation) and for the Hizbollah attack on Israel to get Afghans suitably enraged. At that point, the Taliban will call upon the 300,000 men who used to serve in their army and police force, to lead the population in a national uprising. This will bring the government down, and the Taliban back to power. That's the Taliban explanation for their timeout.