There is a pretty interesting discussion of drone strikes going on at crookedtimber, you all should check it out.
I'm torn on drone strikes, so what follows aren't really conclusions about them, but rather examinations of the tension in different ways of looking at them.
The Pentagon view appears to be that they are much more targeted, much more accurate, have less risk for our soldiers, and cause much less collateral damage than bombing strikes. From that perspective they sound pretty good. If we have to get at some known terrorist organization, some known terrorist, or some clear military target near civilians, drone strikes seem like an excellent choice.
Given the choice between bombing and using a drone, I would think that using a drone is morally better almost all of the time.
However, I worry that from an institutional perspective, the relative ease, saftey and lower level of collatoral damage means that drones end up being used in situations where bombing would not be remotely considered. That could easily create a situation where there are fewer civilian deaths per strike, but still a greater number of civilian deaths total. And also, insofar as each bombing run/drone strike could potentially end up being a diplomatic disaster, having vastly more instances risks diplomatic disaster more frequently.
Also the apparent accuracy leads to problematic situations that may not have existed with bombing strikes. The idea of using a bombing strike to kill a 'bad' American citizen doesn't seem very likely. But a drone strike? Apparently the administration thinks that is different.
I think ideally I would want to have the military analyze whether or not a target was worth a bombing run (keeping them rarer) and then only after that analyze whether or not a bombing run or drone strike is better (keeping non-target casualties down). Unfortunately I know of no way to do that in an actual human system. Given bombing strikes, I'd rather do drone strikes most of the time, but I'd rather not just let the bombing strikes be a given.