Maybe I'm just jaded because I'm a gamer, and I stare at CGI graphics too much, but no matter how you slice it, CGI looks BAD against a set with living people. Its jarring. I even went back to damage my brain with the Ted trailer to take a look at the CGI. Its good, I'll give it that, but I can still tell its CGI.
However, I am not against CGI. There are some great all CGI movies. But CGI is just nothing special these days when companies overkill it. Scott Pilgrim had the best use of CGI I have seen in a movie in years.