CG has its place. It is a great innovation in film making. Things can now be done that were only ever dreamed about. It really is a wonderful breakthrough. But it is way over used. An example I like to use of a film completely destroyed by CG is I am Legend, I am a huge fan of the book, and enjoyed the previous two film adaptions of that novel. I was really excited when I am Legend was announced, it is one of those films I really, really wanted to be great and was willing to over look all sorts of flaws. But the CG just took it way too far. All the infected were 100% CG and it showed. There was nothing that said the infected needed to be CG, there was no reason they even should have been. We are talking about people infected with a virus, not aliens. People in makeup would have made all the difference in the world with that film. Perfect example of CG working against a film.

In the exact same film, the over grown and abandoned city was also CG, and it looked absolutely breathtaking in my opinion. CG is a wonderful thing, but it can be used poorly and excessively.

300 is an example of a film where CG was well used. It really fit the atmosphere of the film and completely worked. The film wasn't meant to be realistic, it was meant to be stylized. To me it really feels like the Frank Miller graphic novel come to life (with the exception of all the silly additions, which are fixed in my unreleased fan edit). You are completely immersed in CG and unrealistic looking things, but the style of everything matches so it doesn't come off looking out of place.