Global shutter frees up all kinds of flash possibilities with x-sync being relegated to the landfill of history. I suspect most R3 buyers don't really care that much about it, but those that want to do action flash outdoors will see it as a big plus. I'd sure like it for that reason, but probably not a few thousand dollars' worth of like.
For regular sports photography, the R3's rolling electronic shutter is fast enough for me.
