The guys from Chiphell.com managed to score what is claimed to be a working prototype of AMD's Radeon HD 6000 Series graphics card codenamed "Cayman XT." According to the info, the pixellized card is the XT version of the Cayman chip and should be the Radeon HD 6x70 series card, at least if AMD sticks to the rumoured naming scheme.
Unfortunately, the picture doesn't reveal much solid information rather than some speculaction that the card might be as long as the Radeon HD 5870, should have CrossFireX support, and has two DVI ports, an HDMI port and two mini-DisplayPort connectors. The post didn't reveal any other specifications, except that we are looking at a GPU made on TSMC's 40nm manufacturing process.
An interesting detail is that the prototype still proudly carries the ATI brand sticker, something that AMD will probably throw away soon enough. In any case, it looks like more info regarding AMD's Radeon HD 6000 Series family has finally started to trickle out, which means that we'll see more surface very soon.
The thread can be found here.