As a family of 4 -- we went with the black, shows less wear. I might have gone with the white as the USB cable comes in white only as far as I know, so it would have been matching.
I don't know if this is the same elsewhere, but we had to pay an extra $50 for the black version b/c of the demand :wondering
Black border makes the colors more vivid and good for badass gaming and videos. We're planning on getting the black Otterbox case for it anyway so black-on-black made sense.
White is good for looking at a pure image w/o the optical "pop" of a dark border, like illustrations, digital paintings or plain text. It seems more of a architectural, modern utilitarian look to me, which I love too.
I don't know enough of the composition of iPad whites, but we were concerned about fingerprints and scrapes showing (used by kids as well) and the possibility of the composition of white plastic to turn yellow with age (this is not something I know for sure).
why are my posts so friggin' long