Rumors from Hungary, according to this Taiwan blog:
http://www.max2.tw/blog/?p=2728
They're actually about Sony. But, one of the things it says is: "sometime between Jan to Apr next year, Sony is expected to have a 600mm lens to compete with Nikon D4 and Canon 1D4".
Lens vs camera body? Don't know if that makes sense to you.
That site also has other rumors re Nikon and Canon, in case you're interested.

