Black's got a cooler environment, but White has much better Pokémon.
Maybe he wanted Reuniclus, Braviary and Zekrom over the goth, the vulture and the Crotch-feather Dragon? That was a factor in me getting White over Black for myself. (My sister is getting Black.) If I had to choose between Black City and White Forest I would go with the former. Looks cooler.
Anyways, so long, farewell, alveterzane, goodbye to Gen IV. Parting is such sweet sorrow~
I remember you from bulbapedia!