PowerColor has leaked a couple of HD 6800 pics on its Facebook page. The actual designation was blurred out, but this appears to be an HD 6850. It's also easy to spot the new cooler design slapped on top.
The picture shows a revamped PCS cooler with a sizable heatpiped heatsink and Powercolor went for a 92mm fan.
PowerColor's non-reference coolers have always offered good performance and low noise levels, but we don't have the clocks. If the old HD 5850 PCS+ is anything to go by, the new card should be a pretty good overclocker.
You can find another picture at Powercolor's Facebook page here.