It appears that by 2017 3D flash could be the majority of SSD flash memory. If these chips reach cost parity with planar flash by then we would likely see a wholesale switch to 3D flash by 2018. 3D flash uses larger lithographic semiconductor features and thus reduces the issues facing NAND flash as the feature size approaches 10 nm. This gives flash memory more generations of development as over 100 layer products have been suggested (by Samsung) and 3D flash can then follow the lithographic reduction again to achieve higher densities and lower costs per bit. As the price per bit of flash memory declines it becomes more attractive for an increasing number of applications.

Source: Micron Will Ship 3D Flash Memory – Forbes