An interesting observation from Niall Ferguson, Empire: The Rise and Demise of the British World Order and the Lessons for Global Power (2002), 12-13:

As Defoe observed in his Complete English Tradesman: ‘The tea-table among the ladies and the coffee house among the men seem to be the places of new invention…’ What people liked most about these new drugs was that they offered a very different kind of stimulus from the traditional European drug, alcohol. Alcohol is, technically, a depressant. Glucose, caffeine, and nicotine, by contrast, were the eighteenth-century equivalent of uppers. Taken together, the new drugs gave English society an almighty hit; the Empire, it might be said, was built on a huge sugar, caffeine, and nicotine rush – a rush that everyone could experience.

I once wrote a paper in grad school about the advent of coffee in Europe. They posted it online, and I discover that it is still there! An excerpt:

Why did coffee become so popular, and come to fulfill a “progressive” social function? Why not tea or chocolate, or, as alcohol was never banned in Christendom as it was under Islam, wine or beer? One suspects that coffee may have become “fashionable” somewhat randomly. It was cheaper than tea and more caffeinated than chocolate (as contemporaries observed, it tended to be more caffeinated than tea as well). It is of course a stimulant rather than a depressant, which makes it more conducive to conversation (and some regulars at coffeehouses, like Voltaire, would consume up to fifty cups a day), and does not leave one with an alcoholic hangover. Coffee did have its detractors (who claimed it was nothing more than a slow poison), but its proponents were equally willing to extol its benefits, such as its ability to ward off plague or to dispel noxious odors.