The Dust Bowl: how's the recovery of all that topsoil going?
Soil is not a single uniform material. When wind erosion takes hold, as in the infamous 'dust bowl' of the 1930s, it is the uppermost A horizon, and to a lesser extent the B horizon that is mainly lost. The lost soil takes with it most of the organic carbon, and it is this component that is most difficult to replace. 

Rates of soil loss are primarily factors of the underlying geology and climate. A wetter and warm climate will regenerate soil very much faster than a cold dry climate. Basalt and shale will break down into soil much faster than, for example, quartzite or granite. The rate of rock weathering is not quite the same as the rate of soil formation. 

As a first approximation, rate of weathering = rate of soil formation + rate of mass loss by various processes.
Wakatsuki and Rasyudin (1992) Rates of Weathering and Soil Formation, Geoderma, V52, 3-4, gives a good assessment of such rates.
Their best estimate is that soil formation occurs at 370–1290 (mean = 700) kg ha−1 yr−1. Or roughly 0.3 mm per decade, excluding the lost organic carbon. This is equivalent to about 3 mm of new soil generation since the great dust bowl. 

In other words, no, the lost soil is nowhere near replenished yet. Moreover, the impact of climate change does not bode well for the future of soil regeneration.