I just had a hands-on and ears-on and pants-in with the Sony KDL-40ZX1, which I declare as the first official superdupercool product to come out at IFA 2008. The 9.9mm screen picture quality is really amazing, crisp, and ultra-light. The design, while it's not OLED thin, is the best I've seen on any TV so far, sleek, simple, and absolutely lickable. The best thing, however, is that this is not a prototype but a real product. The lighting technology is smart and surprisingly effective. Updated with expected price.
The good: they managed to get to this thickness thanks to a new LED lighting technology that is not behind the actual LCD, but on the four corners. Using some optical device, the powerful light from the corners gets distributed evenly through the whole screen. I couldn't appreciate any uneven lighting.
The bad: probably the price. On first hands on, however, I have no complaints. This feels like a true object of desire with anyone with the pockets to buy it.
Bottom line: Sony's really got a winner here, even while I imagine the price would be as out of this world as the TV itself. While last year we saw some comparable ultra-thin prototypes from the likes of Sharp, those are not going to be available until 2010. The thing that sets the Sony ZX1 is the fact that it's a real product that anyone with a big badass credit card could buy.
Update: According to IT Wire, the price of the Sony KDL-40ZX1 would be US$4,500.