I think he'll step down in his mid 80's and groom his son for the job. In Lou's mind, Lou = the NJ Devils and no one, not even the new owners have the cajones to force him into retirement. I firmly believe he thinks he's got enough clout to stand toe to toe with them, based on what he's done for the franchise.
Lou basically runs the organization. No one will fire him. He'll retire when he's had enough and his ego calls it quits, and that likely won't be until he hits his early to mid 80's.
As a Giants fan, this reminds me of George Young in the 1990's...bad drafting, bad acquisitions, no "good" young talent waiting in the wings, a strong indication that the game had passed him by, but Young stayed on board despite his failures and had a massive ego that prevented him from retiring. Young had carte blanche all because of his past accomplishments (2 SB's) and turning the franchise around from a loser to a perennial contender. Same as Lou. Not sure if Lou's ego is as big as Young's was, but in all other cases the comparisons are strikingly similar.