Apparently they believe that "the Taliban is not monolithic. Reports out of Afghanistan reflect a splintering among Taliban leaders, with some offering to take part in a democratic system and allow girls to go to school." More [1] here. "Our view on Afghanistan: Talk to the Taliban?" from [2] USA Today, October 29 (thanks to Jeffrey Imm):

Negotiations might help as part of broad strategy to defeat al-Qaeda. A new, once preposterous, idea is gaining ground: Negotiate with the Taliban. Yes, that's right — the fundamentalist Islamic extremists who once ruled Afghanistan, who harbored 9/11 masterminds Osama bin Laden and Ayman al-Zawahri and their terrorist training camps before the U.S. invaded Afghanistan, and who continue to be al-Qaeda's allies and protectors.

After the invasion,Taliban and al-Qaeda leaders fled to Pakistan's wild northwest region, where they launch attacks on U.S. and NATO forces in Afghanistan. U.S. intelligence agencies say any new attack on the U.S. would likely originate in the Taliban/al-Qaeda training camps in Pakistan.

Yet opening communications with the Taliban is an option being considered by a range of leaders and experts, including the former U.S. commander in Iraq, Gen. David Petraeus, who's now in charge of Iraq and Afghanistan as head of Central Command.
[...]

Talking to the Taliban might be a long shot, but perhaps not quite as long as some suspect if the goal is simply to get its leaders to betray al-Qaeda. On Tuesday, Pakistani and Afghan political and tribal leaders agreed to establish contacts with the Taliban. Saudi Arabia has already facilitated informal talks.

Further, the Taliban is not monolithic. Reports out of Afghanistan reflect a splintering among Taliban leaders, with some offering to take part in a democratic system and allow girls to go to school. It's not unimaginable that they might, with the right pressure or incentives, help deliver al-Qaeda leaders. The point is that no options are possible unless explored.
[...]

The U.S. badly needs a winning strategy in Afghanistan — one that does not cripple the U.S. economy and military for many more years in pursuit of the unattainable. Talking to the Taliban? Time to hold our noses and at least be open to the idea.