List of confirmed HG&SS news:

+Both Kanto and Johto regions appear in the game.

+Groudon, Kyogre, & Rayquaza can be met and caught at level 50.

+The Pokeballs that where made from apricorns in Gold Silver and Crystal are back.

+Apricorns are now stored in a case.

+New PokeGear and map.

+There is a Red Gyarados in the Lake of Rage.

+The Battle Tower is now the Battle Frontier.

+A new area west of Cianwood City is now a Safari Zone.

+All 492 Pokemon are capable of following the player as like Pikachu in Yellow Version.

+There will be an Arceus Event where it you trade an arceus from Diamond, Pearl, or Platinum, and then take it with you to the Ruins of Alph, you will get to chose either a Giratina, Palkia, or Dialga all of with are at level 1.

+You could get a Notched-Ear Pichu. (Event)