@brandon The *real* difference is getting freshly roasted coffee beans. That's night and day.
As for getting beans instead of pre-ground: I do find there's a noticeable difference (I think it's got something to do with the natural oils in the bean, myself) but it kinda depends on what you're getting. Like, if you get really old beans they probably won't taste better than something you bought freshly ground. So lots of variables.