From a physical infrastructure perspective, the two-tier storage model (fast SSD + deep SATA) will become more prevalent in data-centric applications (including big data and HPC). Applications that traditionally relied on tape, such as backup and disaster recovery, are increasingly using disk-based solutions.
What is more interesting is how these disparate tiers of storage will be abstracted and delivered as services. Rather than having capabilities bundled in the hardware, software-defined storage will offer administrators the ability to programmatically control how physical resources are deployed, configured and managed. The control plane, rather than being within a single storage box is integrated across the entire storage system.
Tighter integration between applications and software-defined storage will allow appropriate storage media (SSD, SATA) and configurations (e.g., RAID levels, erasure coding) to be used according to application needs. Also, since flash drives can be used as cache as well as data, SDS systems will allow administrators to programmatically control whether an SSD drive is to be used as data or cache, and set the priority levels for different applications. As software-defined storage gains momentum, the opportunities to leverage the system's flexibility and simplicity are huge.