New carbine?
Though the XM-8 is reportedly done for, HL reports that:
TACOM is soliciting for a new carbine and LMG, presumably to replace the M4 and M249. The bad news? Both call for 5.56mm weapons. Of note is that the LMG is now a standalone, belt-fed system, unlike with the XM-8 family of weapons. I also wonder, since apparently there was no solicitation issued for a rifle, if the Marines will be forgoing their long-barrel rifles for the new carbines.
He also has a look at some of the contenders. Murdoc has more.
