One of the long term problems in computer performance is the time it takes to get data from the processor to and from storage. This memory reduces that time drastically and could mean a big jump in performance.
Intel claims that the technology is price competitive with NAND and DRAM (the kind of memory sticks used inside your computer.) They say that samples will be available yet in 2015.
I imagine it will first be used in hybrid drives – using traditional NAND for long term storage and XPoint for cache. It should be especially useful for video/graphics processing and modeling/analytics applications.