Just came back from eyeing some TVs; I know the specs and components seem identical, but the XBR5 to my eyes displays superior a black level than that of the XBR4. Also smoother detail/motion in some instances. Am I simply imagining things? Went to several stores to compare, so I'm not totally relying on skewed calibration/brightness settings. I found this phenomenon to be true in 3 different stores, and I am certain the bezel isn't simply to blame. I was staring directly at the screen. I know there are clogged xbr4/5 threads, was wondering if anyone can address this specifically.