AfPak and Iran?

I'm trying to figure out what the recent meeting between the leaders of Iran, Pakistan and Afghanistan might mean for the stability of the region. It could be bad as indicated by the following citation:

World Agenda: Tehran summit could be a turning point - Times Online: "Iran tried to use the summit to bolster anti-American feeling by insisting that the presence of foreign forces had not stabilised Afghanistan. Ayatollah Ali Khamanei, Iran’s supreme leader, told the two visiting presidents that “the United States is hated by the peoples of the region because it is considered responsible for these problems”. That appears to have cut little ice with either man, however: neither has any reason to alienate the United States at the moment."

But it could also be good and in time mean a possible exit for the US and NATO from the region. Iran might be trying to figure out if there is a possibility for them to aid in the stabilization of the area based on the much higher credibility and trust for Muslim agents and the principle of subsidarity.