It would likely be a replacement for applications where low latency and non-volatility are required but size is less important. A microcontroller with a good sized chunk of UltraRAM could allow for a type of Harvard architecture where program code runs right off of where it's stored. You can have the microcontroller shutdown completely and start right back up where it left off with NV memory, just write the registers to memory right before shutdown and load them back on boot. You can have very power efficient devices that never really have an off state because they are always hibernating when they aren't doing anything.
