The short answer: yes.
Quite frankly, we're a bit surprised it's taken this long. Like all other premium automakers, BMW has made boat loads of cash off its SUV lineup. Even cargo space deprived CUVs like the X6 have been wildly successful, hence the newly revealed X4 and the upcoming X2. Soon there'll be X models 1 through 7, literally something for everyone. But will it stop there? Could there ever be, say, an X8? Possible, but unlikely. The X7 actually does make total sense, especially for the North American market.
The strong-selling X5, currently BMW's top dog SUV, does offer an optional third-row of seating, although it's not especially roomy. Best leave it for the dog. Audi has its Q7, which comes with a third-row standard, but even there it's a tight fit. And this is where BMW sees an opening. Instead of Audi being its chief German SUV rival, it wants to go up against the Mercedes-Benz GL and even the Cadillac Escalade. There's money to be made here after all. If you're going to build a big SUV, might as well go all out, although the X7 probably won't be as off-road capable as the Benz or Caddie. But that's ok. It doesn't need to be. An X7M would be a more than suitable alternative.