Wow, good in The Pokemon Company and Game Freak to go back on their earlier opinions of whether or not these games should come to the eshop. They were very against the idea due to the nature of the games and them wanting to keep the games in cartridge form to preserve the aesthetic and appeal of link trading between gameboys.
Glad to see them succumb to fan demand and lose a little of my respect. These games are fine, but this is unnecessary and they should stay in the past where they belong.
*disappointing slow clap*
I've never heard them say they wanted to preserve cartridges and link cables, but that's not very reasonable anyway since those things are obsolete. They managed to preserve the core concept of trading and battling with people out in the real world, so I don't think they've gone back on their opinions. Plus RBY and FRLG aren't playable on current hardware, so this opens the originals up to a completely new audience. The decision makes perfect sense.
I can't be the only one who thought about this (apologies if I overlooked the answers) - but what about:
1) Special Attack/Special Defense being separate stats?
2) Dark/Steel/Fairy type Pokemon and moves?
3) Abilities?
4) Type effectiveness (e.g. Bug weak to Poison, etc.)?
5) In-game calculations (e.g. critical hits, etc.)?
6) Pikachu being fat?
7) Dragonite using Agility and Barrier perpetually against your lesser-level Venomoth while it dies from Poison Powder?
7) MORE!
From the sounds of things, they're preserving the originals as much as possible with the obvious exception of trading and battling, so all of those things will probably stay the same.