Rose and Behm have shown in their November 2014 article in The American Journal of Psychiatry that 12 weeks of a combination of varenicline 1 mg twice daily combined with bupropion 150 mg twice daily, led to substantially improved abstinence rates for highly nicotine-dependent smokers.
Most smoking cessation strategies have led to quite low abstinence rates. A typical outcome would be a 25% probability of quitting after a determined attempt. This is the first study I've seen that shows a strategy that leads to a 50% abstinence rate. In fact, they found that the combination works best for the heaviest smokers who were most addicted.
With smoking cessation, as with many other problems, I think that if a pharmacological strategy is considered, why not try the most effective strategy first? Why not try this combination first, rather than trying one much less effective treatment at a time?
Some remaining questions I have about ongoing management would be to question whether long-term varenicline could be necessary (e.g. for a year or more).
And, with smoking, a big question now concerns the potential benefits and risks of e-cigarettes. These are probably good harm reduction aids for many smokers, but on the other hand are addicting on their own, and could initiate dependency problems in young people who try them before smoking at all. Overall, I think e-cigarettes are an important positive development to help people quit smoking, and also to help deplete the tobacco industry further.