Nintendo Hong Kong has put out some details about the upcoming Pokémon Bank update, specifically in regards to the Generation 1 transfer. First, Pokémon will likely have 3 max IVs. Their nature will be random and there is a chance that the Pokémon will have their Hidden Ability. It will also have a unique GameBoy mark
The National Pokédex will sync up with the games you use with Pokémon Bank, listing the Pokémon you have seen/caught in each game and combining them. It will list the games that you have each Pokémon in. You don't need the Pokémon to be deposited into your Bank in order to register them in the National Pokédex. Finally, it confirms that you can send Battle Points again.