I'm sure Ep7 will still have a lot of cgi in it. It'll simply be the way Abrams utilizes and combines physical stuff with digital that feels more true to the OT, I'm guessing.
Also, there appears to be confusion on the whole 2k/4k thing.
All movies shot on 35mm or one of the various digital cameras only have their digital vfx shots rendered at 2k. Even if the movie is finished as a 4k DI, the fx shots are still rendered at 2k and then upscaled to 4k. It's only the non-vfx shots that truly stand to benefit from the 4k finish, which is why movies like The Hobbit are only finished as a 2k DI.
The only exception to this is when a digital effects shot needs to match up to footage shot in a larger format like Imax. In those situations the Imax shots are rendered at a much higher resolution. 5.7k is the number I've heard bandied about.