The Next Generation Service Weapons (NGSW) is still in kick the tires and look for a silver bullet to solve improvements in body armor and deficiencies in command and training.
"So for the Next Gen Squad Weapon, the Army doesn't just want bigger bullets, longer range, or lighter weight, though those are all welcome. It wants hand-held smart weapons with the electrical and data connections to plug into high-tech sights, including technologies that can correct a soldier's aim amidst the chaos of combat."
The likely candidates are in the 6.5-7mm range. I don't see the 6.8 SPC as a candidate as it's limited by the M16/4 platform. Particularly it can't be used with longer bullets needed for accuracy and to penetrate body armor. The M16/4 platform is a nonstarter as the army wants a high level of integration with "advanced electronics". {Maybe even the ability of REMF commanders to choose targets?} Some of the integration is off the shelf already. e.g. SIG SBT and compatible scopes. But it's far from the science fantasy the Army wants. The USMC is currently procuring off the shelf weapons, and waiting on events; while relying on tried and true approaches of good training and command. Meanwhile the Army is wasting $B on successfully more costly boonedoggles.