Is there any actual POWER core ip out there that people can build on or experiment with? Yes, the ISA itself is open, but last I looked that was it. I think RV's availability of implemented cores (even if they aren't the most cutting edge or high performance) is helping it build some momentum. Whether that's actually "ARM-killer" momentum remains to be seen, and might well not be... but I don't think I'll write them off quite yet, just based on IBM's long history of failures to position and market POWER well.