No one. It's just a gimmick, a way for Apple to now start an (expensive) $99+ battery replacement program. I don't know of anyone who uses a notebook for 8+ hours without plugging it into an AC adapter.
Expect this gimmick battery scheme to trickle down onto the MacBook and 15'' MacBook Pro with the next hardware updates.
it would make more sense on a smaller notebook. you could drain a battery on a long plane ride, but even my 13" is a little big for the plane i can't imagine a 17".