Speculation starts up again
Over at NL, Keith was given some information at the focus show in UK about the upcoming 1Ds4. He was told he wouldn't have to wait long and it would precede a 5D Mark III.
It is noted the source could have been fed a line to keep people guessing.
I personally haven't heard anything different than the late 2011/early 2012 I've been told in the past.