This thread is for discussion of only Victini, Zekrom and Reshiram, discussion of other legendaries belongs here, because they were released at a later date.
Reshiram is only obtainable in Black Version, whereas Zekrom is only obtainable in White Version.
That oughta do it.
What'cha think? The white one is Reshiram, and the black is Zekrom. The black one reminds me of a monochrome Palkia...
I've added Rukario's pictures of the individual Pokemon to thumbnails.
Both Pokemon are apparently Dragon-type. No word on if they'll have another type or what it would be.
Zekrom may possibly be part Electric type, but as of yet it's still unconfirmed.
Zekrom is definitely Elec/Dragon, and Reshiram is now confirmed as Fire/Dragon.
For the last time, Zekrom=White, Reshiram=Black!