The 6850 is a quad-core Kentsfield chip that bears the 'Extreme' moniker, thanks to its 3GHz clock speed and 1333MHz front side bus. It's built on 65nm, like the rest of the Kentsfield family, and it will sit above the QX6800 in Intel's range. The 6800 is clocked at 2.93GHz and has a 1066MHz FSB. The QX6850 will be perfect for Intel's new eight-core gaming platform, we suspect.
With a little additional LN2, the chip was able to get up to 4.8GHz with a 1640MHz FSB, which would make for a pretty sweet gaming machine - assuming you can afford the wages of a man-servant to keep the cooler topped up whilst you spend all evening gold-farming in Azeroth.