As to how many kinds of Taliban there are, and where, when the Taliban were forced out, they obviously had to go into a clandestine mode. That makes it all the more difficult to say who's who.
From the reports I've read—and you probably have access to more secretive ones than I do—there are actually about four groups that have splintered off, with different regions of responsibility where they have almost independent actions. There have been reports that in some regions the Taliban has said they will not attack the schools because the schools are popular with the population and they don't want to alienate the population. In some other sectors, you've had the Taliban shooting teachers and attacking the schools.
Actually, to say “neo-Taliban” is probably a better way of differentiating them from the actual movement that was in power first off. Secondly, it's very fragmented.
What you obviously know already is that the Pashtun population is on both sides of the border, the Durand Line. There is a big Pashtun population in the tribal agencies and in the autonomous regions where Pakistan's government sway is very limited. These tribal populations are interconnected, and be it for insurgent activity or for economic activity, there's a lot of activity going through that border and it's very hard to control.
What we do know is that the leadership of the Taliban operates openly from Quetta, Pakistan. The week after Vice-President Cheney was in Pakistan, you all of a sudden had your first arrest of a major Taliban figure.