The closest I've seen to encouraging news about the U.S. role in Afghanistan is this piece from George Friedman at Stratfor.com that describes a strategic debate between Gen. David Petraeus (CentCom commander) on one hand and SecDef Gates and Pres. Obama on the other. (The piece also has about as good a thumbnail sketch as I've seen of how things are -- at this point -- turning out better in Iraq than anyone could have believed possible in 2006, though I think Friedman gives somewhat more credit to U.S. tactics than is due.)
Fresh off a fairly decent outcome in Iraq and having devised the Army's counterinsurgency strategy, Gen. Petraeus, according to Friedman, "is arguing that the strategy pursued in Iraq should be used as a blueprint in Afghanistan, and it appears that Obama and Gates have raised a number of important questions in response. Is the Iraqi solution really so desirable? If it is desirable, can it be replicated in Afghanistan?" And so on. Gates and Obama apparently have serious questions about what level of commitment would be required to establish an effective government in Afghanistan when the essential thing is to get the Taliban to agree not to give al-Qaida bases in the country. That would requires a much less intrusive or long-term U.S. commitment.
Of course, as I noted some time ago, more than once, Friedman actually favors a military withdrawal from Afghanistan and relatively low-key intelligence and special-forces activity against al-Qaida in Pakistan. Maybe he's seeing the possibility of an outcome closer to what he wants. But he usually looks at situations pretty cold-bloodedly.