After clocking 30 minutes into WiiFit, I can say with utmost certainty that
this comic is 100% accurate.
Pretty amazing stuff - the "step exercises" I was expecting, but 12+ yoga exercises that all revolve around maintaining perfect balance while doing them and have actually left me pretty sore afterwards, a jogging simulator that actually makes running on the spot kinda fun and using the balance board to simulate skiing were all pleasant surprises.
Looking forward to putting 30 minutes a day in for a month and seeing what comes of it.