I love CG. The atmosphere is very energetic. Lots of hustle and bustle and excitement. Dress code is resort casual- you will see people very dressed up and you will see people straight from the theme park.
I don't know how often the menu changes, but I know there is some consistency from visit to visit. I had the Tamarind Beef for each meal. The menu is eclectic, you should check it out on Deb Wills' site:
http://wdwig.com/menu/menus.htm
As you'd expect from the name, this is fairly avant-guarde, West Coast-style cooking. Not what you'd call a "meat and potatoes" kind of place. But it's not a place where you'll go away hungry, either. Appetizers, entree and desserts were all excellent, and they have a fantastic wine list.
Our servers have always been very knowledgeable and helpful, expecially with wine selection.
We'll be there a week from Monday, and I'm already getting excited about it.
Oh, did I mention the incredible view? Try to eat there during MK fireworks or, if you can manage it, a thunderstorm. (Disney doesn't release its schedule for those, though.)