If Apple moves in, they will most likely build themselves a
whole new building in the side lot along St. Charles. That leaves the funeral home for a smallish urban-format Best Buy.
I'm not sure if there's enough parking at that site for both stores, but if the landlord works with the city to open up more street parking, it could work. Apple is surprisingly flexible with parking requirements.
What I don't know is if Apple wants to be next to a Best Buy that also sells computers, phones, and music players. That might be a little too much competition. The intersection is also not what Apple usually chooses when they open new stores... they like high-volume retail areas, so if they opened a store in the City, it would be more likely to go on Magazine or in Canal Place.