Hopefully, this will get more traction than OpenSPARC did. I was really surprised that one didn't get adopted heavily. It runs Linux (and Solaris and OpenBSD), is multicore, CMT, low power.
There is also the RISC-V ISA (http://riscv.org/) being developed at Berkeley and the lowRISC SoC incorporating a 64-bit RISC-V CPU (http://www.lowrisc.org/) by a team in Cambridge.