Over three hundred people have died violently in the south in the past two months. Most of these were Taliban fighters. The Taliban is still popular in parts of the south, if only because this is where the Taliban came from. The severe rule of the Taliban was based on customary tribal rules followed by some of the southern Pushtun tribes. So these tribes are protecting a lifestyle, not a political movement. It's further complicated by the growing power of the drug gangs, who often can support the Taliban and their drug business at the same time. The tribalism is so insular and hostile to "outsiders" that even economic development programs are opposed.
The "national" government in Kabul has never controlled the southern tribes in any sense that Western nations understand it. There have often been understandings between the central government and the tribes, quite similar to treaties between separate nations. The central government understands this, the American military leadership understands this, the US government understands this, but the media, in general, is pretty clueless on this subject. This is a largely self-inflicted wound, as the reality of the situation in Afghanistan does not make for good (that is, exciting and easily sold) stories. But portraying the situation as one of national disintegration and constant rebellion does sell. And that's what gets shipped out of the country by most journalists.