Leave it to Nolan to not only make the greatest superhero movie of all time (Dark Knight, duh!), but arguable the best Sci Fi movie of all time to go along with it. To explain anything about the film story-wise would spoil certain elements. I think the best way to go into the thing is to not know a single thing about it.
Start is a little slow, though it picks up and never stops half-way through. Only one guy left to the bathroom in a packed theater in Manhattan. That never happens. There were only a rare, few bits where I'm the CGI was evident. Though it wasn't distracting enough to ruin the movie and happens early on.
There's a lot of ideas and interpretation of the ending. I think this is an excellent read to sum it up:
I suppose! The start was the only place where I could kind of tell it's CGI and it briefly put me out of the movie (a short scene when Leo and the girl are sitting in that cafe outside). But I can't complain!