as per wiki
PowerPC - Wikipedia, the free encyclopedia
Given that powerpc chips are still the market dominant server chip, you may be writing the architecture off a bit quick.
I'll make an obvious guess and assume the unknown future 'new' quantum leap chip architecture will be backward compatible to the many OS that run on powerpc chips.
I honestly don't know if the 'whole' software will need to be rewritten in the future. I hope not, it sounds expensive
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eaglemmoomin, you sound like you know what you are talking about, from what you know, do you think there is a problem that LM and the major air forces have missed?