It really is John Woo's Red Cliff.
It's like John Woo took the story from the book and just butchered it and mixed in some Dynasty Warriors in it. When I saw Guan Yu fighting like that I was pissing my pants laughing and same with Sun Shang Xiang. There was probably only like 2 parts in the whole movie that portrayed the scenes accurately from the book, which were when Zhuge Liang collected the arrows and when Zhou Yu's childhood friend came over to spy on him.
7/10? Yea, but only for its own story and action battle scenes.
I guess that's why they call it "John Woo's Red Cliff".