Over at MacRumors several people say they saw a mention of a new Aperture in the live presentation for the new MacPro. Let's hope!
Not exactly - during the showcase of the upcoming MacPro (to be released in December, according to the presentation), there was a case study of a pro photographer that was using the new MacPro with a version of Aperture that was modified to take advantage of the new machine's features. I am paraphrasing from memory. They did not specifically say anything like the "preview version of Aperture 4" or something tantalizing like that.
If they are going to release new versions of the Pro applications, I would imagine that they will coincide with the launch of the new MacPro.