Skyrim aslo gets a new engine.
Btw could someone elaborate how does RAM improves visuals?
Or in general what processors and video cards are accountable in a game?
Id be greatful, there is a little mess in my head in this question:P

The reason i tink Battlefield will be a bad game is because the only thing people talks about is the graphics. We never hear about actual gameplay that will probably be like the same as every FPS the last ten years

RAM improves visuals in 2 main ways 1. It allows you to have fast access to your assets (models, textures etc) so the more RAM you have the higher quality and number of assets you can use in each frame/scene, so for example with more RAM you don't have to use as agressive streaming so you will have less popin effects (which is when objects suddenly appear or change to be more detailed as you get closer or the game loads) have more objects on screen and use higher resolution textures etc on objects.

2. As the frame is "drawn" it has to be stored in RAM and uncompressed image files are very large especially when you add in effects like anti aliasing and other effects which take up RAM so the more RAM you have the higher resolution and more post effects you can have.

What Zarx Said

Only I believe things like Anti-aliasing and Texture resolution performing at an optimal quality are more dependent on the videocard ram. 
Which is still ram I guess.

quoted 4 truth

yes it is a type of RAM and also as the 360 has unified RAM...