Honestly, when the anime went out of 4kid's hands and off of local free tv, I started to ween off of the series a bit. Since then, I've seen very few episodes after the cut off point, and I hate it to admit it, but my interest in the series has also gone shallow. I got the RS, PD (didn't care much for 4th gen so I didn't get Platinum), HS/SS, and B/W games due to interest in a new gen and a bit of obligation.
I beat B/W and EV trained/IV bred a lot of pokemon, so I was still very dedicated to the series. However, I lost the game very early on and from then on, I went cold turkey with Pokemon. Because of that, I skipped B/W 2 entirely.
I want to get X or Y only because of the fact that it's a 3DS pokemon game, but will I miss anything from B/W 2?
Yeah, I know, I've got a kiddie heart. Man, those saturday mornings were the days... ;_;
It's an entirely new region, so it's not likely you'll miss much unless there are returning characters that play important roles; something that isn't usually present. So I'd say you wouldn't need to, although I'd recommend playing it for fun anyway.