The TH-50PX80U is the bigger brother to the 42PX80U.  Both televisions are on sale at Sears.com for pretty darn good prices.  The 50PX80U is retailing for $899, while the 42 inch version is selling for $699.  This is part of their advertised specials from 1/18 – 1/24.

AVSForum has a thread going on for people who are looking to buy it.

As far as specs:
-Dynamic contrast ratios are up to 1,000,000:1
-new anti-reflective filter; lead-free “Tough Under Force” panel is resistant to impacts and scratches
-Built-in SD card slot with Photo Viewer/Gallery Player software
-x.v. Color and Deep Color (HDMI 1.3 features)
-24p native reproduction
-Game Mode auto-adjusts image quality suitable to games and includes anti-image retention
-Viera Link, now compatible with Onkyo and Yamaha home theater systems
-At least 3 HDMI inputs
-THX Certification
 

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