The take by @gruber is that the commercials are meant to assuage doubts of switchers and let folks know that if they do come to the Mac; Apple is here to help.
I think the larger point and purpose (if you look at the subtext particularly of the child-birth ad) is that Apple (and her advocates) have always been there to help. Everyone I know that feels strongly about the user experience on the Mac (or is willing to engage in an argument over which platforms are better) has been “that person” that everyone they know goes to for help on whatever platform.
The creation of the “Genius” is really just a codification of the same spirit exhibited by most of the long-time Mac users that I’ve known. The Sunday afternoon MUG; let’s have a party with computers.
The folks that have always backed Windows, well, not so helpful on the whole. Kind of like their OS.