I'm pretty sure it's not going to be exactly the same. They might make it 3d mapping 100%, whereas in VII you traveled mostly on pre-rendered backgrounds. It isn't until the world map you can turn the camera and look around. It was the great step out of Midgar!
The battle system will probably be redone but I don't really think Materia is being replaces with a spree grid. Even in Crisis Core you equip materia. I think they will add more and maybe make a change. Still I don't think we'll see a grid or license board. What is the point in magic rocks if you can't use them?
As far as outfits go we'll see some. I don't expect the graphics or dialog being the same. English translators have come a long way. We might see less dialog due to limiting voice acting. They might even add different places as well.
It's great that we are seeing a remake. I know it's going to be a long wait. Nearly 20 years of playing this game I have to say lately it's gotten old. I try to play it but the graphics are not all that great. Also there is just nothing to do anymore.
I'm gonna love the bike scene. The gold saucer battle arenas and chocobo racing. Boss fights I'm looking forward to seeing is Midgar Zolem, Ultima Weapon, Hojo, Demons Gate, and Sephiroth. All the characters are gonna look younger I think.
My views on Genesis : I don't mind him. He held his own against Sephiroth.