I am also impatiently waiting for the new iMacs to be announced.
I noticed this link from 9to5mac. In the update at the bottom of the article, it shows that the FCC won't get pictures of the new magic mouse and keyboard until Feb 10, 2016. Isn't that a clear sign that we won't see the new ones until February 2016? Any thoughts on this? I doubt the FCC would approve of things without the pictures of the product, internals and manual.
I pray not, but this makes me think we have to wait till Feb 2016
http://9to5mac.com/2015/08/15/magic-mouse-2-bluetooth-keyboard-apple/