This says it is a 1.3x, but I suppose nobody will know for sure until tomorrow. I can't see Canon making a 16mp full-frame, or a full frame that could do 12fps, though, so I am fairly confident that the speculation is correct.
http://philipbloom.co.uk/2009/10/19/canon-1d-mkv-imminent/
Also, the IQ between a 5D mkII/35L and 40D/50 1.8 should be pretty significant. There's a reason people pay for good glass.