Until the Android OS supports 64bit its not really important that the processor do it. Likely next version of Android will (not the one coming in November) but next year.
It's not a big deal. At the moment it's a gimmick becuase there is nothing that can take advantage of that architecture at the moment. There hasn't been anything in the year since Apple released their A7 chip. The phones we have now are plenty fast and are overkill.