Ruby and Sapphire will be remade as TerraRuby and AquaSapphire.
FireRed and LeafGreen will be remade as BlazingFireRed and GrowingLeafGreen.
*Having your Pokémon follow you will be optional. FALSE
*Emonga will be the evolved form of Pachirisu. FALSE
Diamond and Pearl will be remade as ShineDiamond and GlitterPearl.
HeartGold and SoulSilver will be remade as PureHeartGold and ShiningSoulSilver.
In PHGSSS, the Sevii Islands will be accessible.
The Battle Zone will be much larger in SDGP.
Player characters will be customizable. You can also choose your own battle theme based on how powerful you are.
Things I'd like to see but might not happen
I'd like to see the male and female trainer be boyfriend and girlfriend at the start of the game, but then break up and become rivals. Then they get back together at the end. The players of Black and White are older, so this might be possible...