It seems as if Carmine became boss of the Lupertazzi family in the last episode, as Butch looks to him before answering about Phil's location.
In a previous episode, the one where Gerry Torciano was killed, it was assumed that Doc Santoro ordered the hit. As Carmine said to Tony, "Doc showed a lack of respect." Carmine made it clear that he did not want to be boss at all.
Now, as I think others have stated, could it be that Carmine played one off of everybody? In that, he ordered the hit on Gerry, and then acted like he didn't want to be boss? Let Phil and Doc battle it out, then wait for the old-geyser winner to fail. Carmine knew that his perception to others was of an idiot, so he knew that others would not perceive him as a threat. Possible, no? Thoughts?

No, Butch becomes Boss of the Lupertazzi's. He gave Tony to okay to take out Phil and also made the final decision on what to do with Janice's situation. Tony was only asking for Carmine's input since he had said nothing. Butch was also Underboss of the family and Albie was Consigliere, Carmine was still a Capo down in Miami. Plus he doesn't have that much support in the family from what we've seen.

Regarding the NY power struggle during the early part of the season. Phil stepped down, his protege Gerry Torciano was suppose to step up, but Doc Santoro took him out. Doc had been actinf boss while Phil was recovering from his heart problems. Phil was frustrated being stepped on all his life and killed Santoro becoming the boss again. Carmine was never a factor, he saw what happened when he faced off against Johnny Sack in 2004.

Butch DeConcini - Boss
Ablie Cianflone - Consigliere
Little Carmine - Underboss

Tbf Little Carmine's not really Underboss material I think he's more of a Consigliere it is possible that Albie was allowed to retire after this due to old age and possibly letting Jerry Basile or someone else become Underboss with Carmine as Consigliere