Ian Rapoport was smart enough to retweet one of Carter's comments earlier today:
Things just got real... Real fast. But [I've] been waiting for this day. I promise you twitter fam #hardworkpaysoff
One can only assume that when a practice squad player (who turned down an opportunity to sign with another team) says that he's been "waiting for this day", that it means he's being pulled up to the big leagues. Jermaine Cunningham was placed "Doubtful" on this week's injury report with a hamstring injury- and the hammy is never a good injury in New England. It's the equivalent of the mid-season Foxborough Flu.
Carter's been receiving numerous accolades as practice player of the week and has bulked up to NFL-size and strength over the course of the season. Don't be surprised if he gets the call.