I wish it was a matter of time! Tony Wilen, the current WinUAE developer, has expressed several times he wont add PPC support. Nowadays he only seems interested in making WinUAE bloated by adding a zillion of obscure features normal users wont use. It is a pitty, he is really a very good developer!
Yeah, and this is a great way to thank him for actively developing one of the most extensive and advanced computer emulators there are. The "zillion of obscure features" are there because in the end they are what makes emulation accurate.
Oh well, the thrill of playing 320x200 Quake in 30 fps (or, as someone else suggested, running some shitty emulators or wipeout) must surely be worth the effort of totally changing the scope of the project and adding PPC emulation.