I totally agree with Jeff Wells. The below video of Tom Cruise performing his own Mumbai skyscraper stunt half a million from the ground for Mission Impossible: Ghost Protocol takes some balls of steel but in 21st century cinema-going, some popcorn muncher next December will shout "CGI" at the screen and not believe Cruise actually did it. It's just the way it is. I saw Unstoppable earlier this week and I had the exact same reaction when Chris Pine was performing something daring, but hell I don't know what parts of it were CGI and what were real.