How has B/W changed the metagame?

Sand Rush and Sand Force

I'm still used to the Japanese translation names :3.

I was listing general boosts.

I guess I'll be more general:
rain dance > sunny day in that a single pokemon can get boosts 1 & 2, whereas the same thing isn't possible with sunny day.

But sunny day gives more boosts in general to a variety of pokemon.

Too bad they're all too generally weak to abuse them (although Venusaur and Ulgamoth (english name please, fire/bug moth thingy)) rape).