Roberto Innocenti emails me that he's started a project to deliver a new PowerPC notebook in the DIY tradition of the Novena Project and the pi-top, only significantly more powerful. Apparently he intends to team up with an Italian motherboard producer and will present his project plans at Linux Day 2014 in Milan. According to Mobile Linux News, the laptop will feature upgradeable components such as the video card, RAM, and SDD/HDD. It will also be 64-bit with altivec and multi-threaded capabilities, and will fully support gnu/linux as well as OS X virtualization.
You can follow along with the project's news at PowerPC-Notebook.org. Needless to say, if this became a reality you could knock me over with a feather, but stranger things have happened. Like Apple switching to Intel. ;)