I (thanks) and others have been notified that the NDAs (non disclosure agreements) for the EOS 7D replacement will expire early September.
CR speculates the dates could be either September 9 (Tuesday) or September 12 (Friday), 2014. They also got rumor that a new telephoto lens could be announced along with the EOS 7D replacement.
I always thought that the rumored announcement date in August was a bit weird. It’s hard to differentiate serious rumors from the rest. Photokina 2014 starts September 16, 2014, so an announcement during the first weeks of September makes sense.