The argument is that this year Samsung will be moving not only its flagships, but its midrangers to mostly metal casings, to which Xiaomi wouldn't have a reply, as it would require some retooling and economies of scale on a grand scope. This would take care of Samsung's most pressing design impression problems, that has plagued the company for the last two years or so.
Samsung, however, will have aces up its sleeve that the competition can't match this year, namely the superior 14nm chipset manufacturing process, and the flexible AMOLED display technology. We already heard that Samsung might be taking on the almighty Qualcomm by issuing its bread-and-butter Galaxy S6 with an Exynos chipset. The analyst, however, confirms that the S6 could indeed ship with a dual-edged flexible display version, and in much higher quantities than Samsung did with the Note Edge, for instance:
To summarise, the Jeffries' analyst expectations are for Samsung to really hit it out of the park this year, ending its long period of restructuring and mobile strategy adjustments. Pushing back against Xiaomi and the rest of the Chinese gang would be done via Samsung's inherent strengths of flexible displays, the 14nm take on Qualcomm, and DRAM chip advancements. Sadly, nothing is mentioned about a radical change in software and services, so we can only be guessing what Samsung has in store for us in that respect, though the wait won't be long, as the MWC expo is fast approaching.