Are we in for a lot of disruption in the short-term? Probably not. There are always stop-gap measures to ease the pain. But it's important to realize where these trends are heading. The ultimate goal of automation has not been incremental productivity increases, but freeing humanity from the need to work altogether. What was once the purview of science fiction novels will likely become reality within our lifetimes.
So what will that world look like? A techno-utopian society where everyone uses their (now plentiful) free time to write poetry, philosophize, and build meaningful relationships? Or an atomized dystopia where the masses are basically anesthetized through a Basic Income and a wide variety of digital distractions? I think we're much more likely to end up with something like Huxley's
Brave New World than Marx's post-scarcity utopia.
IMO, there will not be a shortage of opportunity at the national level. How families and communities seize the opportunity is a different story. The marketplace will change, as it always does, and it will force people and communities to adapt. Those that do will be fine and those that don't will struggle.
Communities are usually rooted in a specific place, so their ability to adapt is limited. Individuals, of course, are free to re-train and move to a new city for better opportunities; but the constant need to be mobile is a big reason why capitalism undermines community. How can one build meaningful human relationships when you're always chasing your next promotion in a different city? It's also worth noting that retraining is a very difficult thing to do, and programs aimed at retraining our citizens have not been successful. People are much more likely to get discouraged and drop out of the work force than to start from scratch.
You also don't evaluate the quality of life, cost of living impact of these companies (although I would argue Facebook has a negative impact on quality of life). Yahoo and Google make me incredibly more efficient than I could imagine being without them, and I do not show up in their employment numbers.
You touched on it with the Facebook comment, but the costs associated with capitalism's never-ending churn are reflected in broken families, declining communities, and shallow inter-personal relationships (which makes them largely hidden). Have all these electronic gadgets really helped us live
better than our ancestors did? I don't think so.