It's been years since I've done music recording as a hobby so someone correct me if I'm wrong -- you can be guaranteed that almost all popular music is pitch corrected in some way. There's Autotune and then there are other ways of pitch correction as well -- Melodyne allows you to manually adjust pitch at a microscopic level. I was able to use Melodyne to perform manual pitch correction that sounded far more "natural" and non-exact than auto-tune.

Of course a lot of folks cannot tell the difference, but to me it's night and day. I couldn't stand Glee for instance because of how auto-tuned the voices were.