Is there that much of a future for magnetic spinning disk? Even if manufacturers could move to 30,000 rpm disks with better areal density, the constraints in the engineering and physical capabilities of magnetic disks will still put them orders of magnitude behind flash-based systems in overall performance terms.
We are also still at the early stage of using flash as enterprise storage. Already, improvements in price and performance, along with longevity, have been rapid. With the emergence of 3D TLC NAND (a faster, denser and ultimately cheaper flash system) as a substrate, we can expect to see this accelerate.