re: Why is Casablanca a top rated movie for you?

I love it. But then again I'm a pretty huge Bogey fan.

Besides that, it has some characters that have a bit of depth and a mixture of good, bad and in between in them.

Rick himself - the cynic opportunist that does have some ideals after all and is able to overcome his own hurt.

Claude Rains character - crooked police chief that shows some humanity but (IMO) is still a highly shady character.

Even the girl someone mentioned upthread. Fraternizing with the Germans but still has enough patriotic French pride to be moved by the anthem.

Plus, Bogart's supporting cast was so great - Sydney Greenstreet and Peter Lorre giving great performances even in smaller roles.

I love it and find it very re watchable.