Due to the censor that prevents Pokémon with offensive nicknames being traded on the GTS, an English language Bulbasaur cannot be traded without a nickname in Pokémon Black and White.
I understand Cofagrigus... but how is Bulbasaur offensive? o.o
Well, thanks to this, I can brush up on my foreign curse words. I do wish it was region specific with the bans at least, it kinda makes trading annoying.