I popped in to note my impressions of the 6020,6010,50PZ800U and 58PZ750U I saw almost side-by-side in my local store, in a relatively dark room. The Panasonics and the 6020 we arranged in a pi shape, the 750U being the center and the 6020 on the left, whereas the 6010 was exactly on the 6020's back facing the other way. They were all fed with 300 on Bluray.
I couldn't tell much difference between the 6020 and 6010 apart from the 6010's skin tones looking slightly more red (brown in 300's lighting). Pricing for the 6020 was +1k than 6010, not sure if justified, probably not. On the Panasonics now, I have to say that the new one is a big improvement, however it is true that the Pioneer has better blacks but not by that much. I feel that the new Pioneers need to be priced competitively to sell well, they don't stand out as much as they did last year.