Demographic Crises
Social and Economic Effects
Here's where the long-term impact of the demographic crises was greatest, and here where it's clearest that the impact was due not so much to the outbreak of plague in 1347-50 as to the cumulative effect of the return of the plague in the 1360s and nearly every decade thereafter for the rest of the century. We can see this when we look at specific communities. We see them recovering after the mid-century plague, and we see them recovering in much the same way they did after other demographic crises. But when the plague came a second time, and then a third, that's when we see towns go into long-term population decline, when we see whole industries disappear from a community, when we see villages abandoned.
Economic effects are easiest to identify. I've already mentioned the abandonmnent of villages, but the really significant effect in the countryside was the rapid shift in the economic and legal standing of the peasants of western Europe. Their position had been shifting steadily but slowly before this. Most particularly, serfdom was gradually disappearing and more peasant farms were held on a money basis—either through outright purchase of land or (more commonly) through conversion of labor services to cash rent. This development was mirrored by a rise in the 15th century of serfdom in eastern Europe (which had hitherto had a largely free peasantry). This change can be dated rather precisely in some communities; where it can, it seems to follow hard on the heels of the second outbreak of the plague, mostly in the 1360s. In later years we see the nobility trying to restore relations to their former state, but by that time too much time had passed, other conditions had arisen, and there was no going back. Western European agriculture would be based on a free peasantry from the late 14th century onward.
The long-term effects on crafts, trade and industry are less clear and are still debated. That there were short-run effects is not in doubt, but other factors enter into the equation when we stretch the time out to decades or a century. Trading patterns, for example, were being affected both by the rise of the Turks in the eastern Mediterranean and by the development of sea routes between the Mediterranean and the European north. Mining, to take another example, was more strongly affected by the natural cycle of old mines playing out and new mines being discovered. Historians will differ, but my own opinion is that there's insufficient evidence to make general statements here.
As for social effects, that is likewise difficult to pin down. The most prominent stems from political effects: a long-term change in relative social status among the nobility and the wealthy commoners. In general, the upper nobility had a hard time of it economically from the late 14th century onwards while at the same time the rich merchant class rose in prominence. On a more local level, we see the rise of the gentry in England, a social class that was not noble but which held land and status, and which exerted political power through membership in Parliament.
In all these cases you should not ascribe the changes solely to the Black Death, or even to demographic crisis in general. Rather, you should recognize that all these trends were in play before 1347, but that by 1380 or so, they were greatly accelerated because of the dramatic shifts in population.