I agree, I doubt there is going to be 64 bit, and new retopo, after all its a revision of Zbrush 4, these added features are more v5, and im sure there would have been a video or two showing this.
One thing that I really would appreciate is when a releases are due, a fix list is available, as to many im sure this is even more important that additional features, new toys are the added benefits in my mind.
In either case there is no room to complain, but only to express a opinion, because these updates are still given for free!, if that was Maxon, we would be paying a good sum for this.