With all the additional 5D Mark III conversation coming about, I’ve also experienced an increase in EF 24-70 f/2.8L II talk.
The latest I have heard is the suspected final prototype is in the hands of the select few for testing. It has the same external zoom and is slightly shorter than the current model. It is also lighter.
There has been an IS version that was bigger and a lot heavier, as well as an internal zoom model, both of which were deemed too big and/or heavy.
There is also a suggestion that the 24-70 f/2.8L II could end up a kit lens for the next 5D camera.