Supposedly, Samsung is already working on a 64-bit version of their new Exynos processor line. This one will be based upon the ultra-high-end ARM Cortex-A50 architecture. This shouldn't come as much of a surprise. It turns out that Samsung made the new 64-bit A7 chip that is the Apple iPhone 5S.
It was obviously inevitable that we would see Samsung utilize the technology in their own designs as well. The only primary advantages of the 64-bit core is that it can address more than 3GB of RAM, and that it can handle multi-tasking better than a 32-bit processor. Of course, the application/software has to be written to take advantage of the 64-bit tech, otherwise, there is no appreciable difference.
Regardless, along with the intel above, we have word that the next generation Galaxy S5 will likely be Samsung's first candidate for the newer 64-bit Exynos chipset. Of course, this should not come as a surprise either. Samsung can't afford to fall too far behind the iPhone in the spec wars, lest they appear to have lost their edge.