We should be extremely concerned about this move and diverging ISA implementations since none of the ARM vendors are capable of acting like adults. ARM Ltd succeeded in proliferating the ARM architecture because they could be counted on by willingly sharing their work with other vendors but all of this comes under threat with a potential acquisition by Nvidia since it comes in conflict with their philosophy of keeping the work exclusive for themselves ...
Even Intel could show some bouts of adult behaviour by adopting x86-64, ABM, F16C, and implement some 3DNow! instructions such as PREFETCH/PREFECTHW even thought these technologies were not originally proposed by themselves. AMD also had to put aside their own ego and do the 'right' thing by shelving much of the 3DNow! instruction set and were faced with an incompatible instruction encoding between their own proposed SSE5 and the Intel proposed VEX coding scheme (AVX) but in the end they mostly embraced the latter ...
AMD or Intel weren't exactly the best of friends but they eventually gave the x86 architecture a politically stable environment while the political arrangement between ARM vendors is a fragile one. Can we realistically expect the same political environment after Nvidia acquires ARM Ltd ?
