You're going to read a lot of yammering about how this is part of a swerve back towards family-friendly Vegas which allegedly flamed out in the mid-1990s. And yet there's been more than enough geared to families -- four of the existing Cirque shows, all those magic shows, almost all those Broadway shows, all those roller coasters, all those animal attractions -- for some time. It's simplistic media shorthand to view Vegas offerings as one thing or another; there's no way for this city to be successful by catering to one sort of customer.
I suspect this will be a pretty smart fit for all the reasons that Phantom works: Everyone knows and loves the music and story. And Lion King has one more thing going for it; while there have been tours of the show, for sure, it doesn't feel done to death. There's no place other than New York in North America to see it, either.
The release says: "Mandalay Bay's production of THE LION KING will be virtually identical to the other companies seen around the globe and will be staged with all of the same spectacular music, sets, and costumes that have made it a worldwide phenomenon."