The humor and music are just incredible, and the gameplay is a fun fusion of action and RTS. I don't think any other game has left me with such a "HOLY COW THIS ROCKS" for a while.
The PC port is really well done. Performance is great, controls are great, plenty of options to make it fit to your PC. And at full HD with anti-aliasing, it looks so much better than the console version.
One thing you should know before playing: the game feels like a free roaming sandbox at times with side quests and exploration bonuses. Don't let that distract you; that side of the game isn't as rewarding. Just play the story and enjoy the heck out of it.