Okay, so I've been without access to a PC so couldn't reply before, so this is a very late reply, but I wanted to address it somehow.
People judging uniformity on W900A sets through the black bars are doing it wrong (I don't know whether that's the case or not) because they have dynamic local dimming; which means 2.40:1 (letterbox) and 4:3 (pillarbox) will be really black because they are not being lit, that doesn't mean their blacks in a practical situation are comparable to modern Panasonic or Samsung plasmas. In fact, it's barely matching (read: not matching) a regular Panasonic series 10 (S10/G10/V10) with factory levels of black, but the bars are "blacker", only the bars, a full frame high range image (with both "blacks" and brighter colors) won't display such results so it's never worthy of the "pitch black" monicker... but the black bars help still in creating an illusion as it's less noticeable in the middle of "detail". Still, pop in the last Harry Potter movie (which is the "goto" stress test for that) and see.
If you were to see that set next to a modern plasma though (or just owning that modern top range plasma), you'd notice it big time due to the depth of the image going on. I know I do, and I had plasmas with lower blacks than the W900 at home.
It also doesn't mean the screen is not full of light leakage/clouding, just that it disguises it so you need to poke further through other means, I'm kinda sure you did, or are going through the process of doing so, but I felt it should be said because of the way it might sound to others that want to get picky with their purchase. The black "kuro black" bars are part of the package, but that's not saying much other than yeah, it looks good (but it's also hiding stuff if the panel happens to be a "stinker").
I really don't think motion is up there from what I've seen of it, Sony needs to pull 120 Hz strobing before we can even consider the hypothesis of diminishing returns, not to mention the method increases motion blur a little for the time being, something the plasmas never faltered and helped a lot with motion.
But it looks good and it is very commendable seeing they're the only ones doing it as of now.