I set up my W900A last week coming from a 5-year old Panasonic plasma, and I was floored by how much deeper the blacks are on this LED set. I'm not sure if that speaks more to how crappy that Panasonic was with its rising blacks, or how good this Sony model is, but whatever the reason it's pretty great.
The past few days I've been tweaking the settings, and most the time I think the set looks too contrast-y, or the blacks looked crushed, but WoW tells me otherwise and I think it's just I'm not used to seeing blacks so dark.
I do see the issues with uniformity and clouding though - although it's not terrible. Honestly, between that and the mild IR from the plasma, I call it wash. Pick your poison.
The lack of buzzing was strange at first. When the first bright/white screen came onto the Sony, I could have sworn I heard a phantom buzzing lol. Like how an amputee can still feel their limb. As odd as it seemed to me at first, it sure is nice having a completely silent set.
I think the WoW disc is about as easy as it gets. Try again. Do the basic setup steps and listen to the Instructions before doing so. Use the bar tests to set black and white levels - that's probably the most important.
As far as W900A specific settings go, I would recommend turning off the Light Sensor under the ECO options. It made a noticeable difference for me. If you don't, the set will automatically adjust levels depending on your rooms lighting conditions - in theory.