Well, there are various members I know on there from Serebii and Bulbagarden. Active wise, CommanderPigg, Piplup, Yoshi-San and quite a few over here on the Bulba side of things are on Tumblr and Serebii wise the only one you might know of on there is Dentogirl/00_pokemanic_00.
Unfortunately, BW isn't a saga that is catching on with most of the internet Pokémon fandom in general for some reason but you will definitely find more BW fans and BW TR fans on Serebii than you will here.
I love Zager. I have always been a fan of his. Yeah, this is really not the place to look if you want to find Zager fans. There are more Zager fans on Serebii but for the most part, it doesn't seem like Zager has many supporters on these forum unfortunately.