[firethief]

It depends on how high up the software stack you work. For most people it won't make much difference, but for some people it's huge. I do a lot of SIMD optimization, and x86 is 128/256/512-bit short-vector SIMD. Arm is 128-bit/long-vector. Even short-vector on Arm uses a different programming model from x86 (the intrinsics are more abstracted from the operations in order to support endian-agnostic operation), and of course long-vector is worlds apart.

I'm not complaining though; we're entering a new golden age for people who like learning the intricacies of ISA's and microarchitectures!