I have to disagree about being the middle man. Deskilling the workforce into an assembly line is a value creating activity, it's what engineers basically do. The typical middle man is simply there to skim some money because there are communication bottlenecks.

Yes, you're totally right - land will get devalued. The older generations in richer countries will lose the most relatively. This is not a bad thing fundamentally (it reverses the rich get richer trend), and is actually what's already happening, but people don't feel it. Every story that is heard about poverty reduction in China is also a story of westerners getting relatively poorer - though in absolute terms everyone is getting better quality of life.