*Due to many of us playing our new B/W copies, news feeds may be short and sweet the next couple of weeks. Also, I still need to post on last Saturday's episode of Pokémon.*
When your ready to unlock Zorua and Zoroark in Black and White, make sure you send over Shiny Entei, Raikou, and Suicune (as well as Celebi) using the Pokemon Relocator in Castelia City NOT the PokeTransfer system that is unlocked after beating the game.
If you upload them using PokeTransfer, they lose the ability to unlock Zorua and Zoroark for some reason. As these guys are the only pokemon which can use the Relocator, it's probably a method for blocking hacked events. To use the Relocator, you have to tell a man in Castelia City the phrase, "Everyone happy simple connection." This is similar to how Mystery Gift is unlocked in the other DS games. Once you do this, the Relocator will be available in the main menu. The guy is in a building on the street which exits Castelia City to the Desert. It's the first building on the left, 11th floor... he's the Scientist.