I've been through every setting - as you may or may not know, putting it into "PC Mode" by renaming HDMI to PC disables most of the picture options completely. This process drops the input lag to 16ms, and it feels amazing for 2D gaming. I'll try all the settings with PC Off and see, but the blacks... they ain't black! Either way, nice blacks are not more important than input lag to me, otherwise I wouldn't've bought this TV in the first place. Just more of an observation than anything. The only time I've seen worse blacks is on entry level LG plasmas - those are just wretched.
Shadow detail is a little crushed, but I bumped up the gamma a bit and now it's awesome. I checked - it doesn't change black levels on things that are supposed to be black. I'm only focusing on all-black fade out screens or letterboxing. The intra-scene contrast is excellent.