It comes down to growth rates. China's economy has been growing at 10%+ per year for several years while the highly industrialized countries have been around 2-3% and are likely heading in to a slowdown and/or a recession.

The growth in the demand for nickel products is even higher than the 10% growth rate, since as their economy and industrialization matures, their demand for more specialized products increases significantly.

We know North America and the US are heading in to a slowdown and/or recession, which means that nickel demand will stagnate or even decline. If China can manage to retain their growth %, or near it, global demand for nickel/stainless steel will remain robust and will be able to eat up much of the supply coming online in the next two years. If, however, China starts to slow down as a consequence of a decrease in demand for their products do to a slowing Western economy, this will have a heavy impact on nickel demand. Thus, all eyes are on Asia.

(as a side note, China's GDP will likely surpass the US as the largest GDP/economy in the world in about 10-15 years)