Hmm..i guess it just depends on personal preference, but really to me i would choose black just because it looks better than White. On the other hand i would choose White & it's exclusives over Black & it's exclusives.
I'm making this decision in the next couple days on which i'm gonna buy only because i decided to wait to buy/play White/Black,Black2/White2 till later down the road since i took a long break from pokemon, so i've decided to replay Fire Red, Ruby & Platinum to really catch back up. Pretty exciting because of the break i took i have so much Pokemon to look forward too.
So my vote goes to White since that's probably what i'll buy