Much as I like MorphOS, the architecture "announcement" seems more like "thinking about thinking about a new architecture". I wouldn't read much into it at this point - I expect it will be be at least 5 years before we see anything tangible on that front.
Looking forward to 3.x, though 
I think 5 years is a bit pessimistic. My guess would be more like 2 to 3 years before the Team is finished with Apple PPC hardware and has moved on to something else.
If all goes well, I would not be surprised if G5 support is released some time toward the end of 2012. Of course that may just be wishful thinking on my part.
Edit: Now that it is nearing the end of the 3rd quarter of 2012, I will have to revise my wishful thinking and say that I hope for G5 support in MorphOS3.x to happen some time before the end of 2014, but if we are lucky, it will be before the end of 2013 instead.
