IMO CGI is the best thing to happen to movies since sound as far as adding realism and imagining scenes that would be impossible without it. But that said, it doesn't make up for basic film making or especially basic story telling.
The judgement of any film or book is whether it is a good story well told. Way, way too many movies these days look like they spent their entire budget on tremendous CGI special effects and left about $110 to pay the writers. Bad dialog, bad directing and overall really bad story telling in a lot of them. If you start with a great story and tell it well then great special effects can really add to the overall movie going experience, but the effects are still just gravy, the story is and always will be the meat.
I like Casablana a lot because it's a good story well told even though the plane taking off at the very end is really fakey looking.
