The universe of 40K is big. And often times the epic gothic grandness is what we key in on. It's the most overt part of the game since it is a major part of the Space Marines. It's their thing to be big, and the gothic trappings add to it. But one of the more fascinating parts of the universe, to me, is the Imperial Guard.
I probably won't play them because I play the Orks and one mob army is quite enough, thank you very much. But there's this cool feel to the IG. They have the cool tanks, they have the cool imagery, and you have to think they have the cool propaganda films.
This film isn't the best (can we learn spelling and grammar people?), and it's a bit long, but it reminded me of why I was drawn to the IG in the first place. They are the natural evolution of modern military to the 41st millennium, and they have cool tanks.