I have it, I just haven't gotten around to playing it yet. I finished the tutorial level, then set it aside to play Tomb Raider. I've heard that it's short and sweet, though. I'll get to it one day.
I put in a 500GB HDD about a year ago. I'm not sure how much I'm using, but I was probably only at ~75% full. I actually deleted more than that, and there are still a bunch of games sitting here. Spec Ops: The Line, Crysis, LBP Karting (one more trophy...

), DC Universe Online, God of War II, Dungeon Defenders, and about 10 more PSN/downloadable games, Beyond Good & Evil, The Cave, Closure, Quantum Conundrum, etc, etc.