There's been a lot of interesting research around file systems for persistent memory.
One that shows a lot of promise is NOVA [0]. Its focus is on making full us on this new type of memory. And it's not just pure research, they are attempting to get NOVA included into Linux kernel [1, 2].
And while talking about file systems, we shouldn't forget about the effort that was put into modifying the existing ones to support DAX (Direct Access) [3, 4].