writes "ARM debuted its new 64-bit microarchitecture today and announced the upcoming launch of a new set of Cortex processors, due in 2014. The two new chip architectures, dubbed the Cortex-A53 and Cortex-A57, are the most advanced CPUs the British company has ever built, and are integral to AMD's plans to drive dense server applications beginning in 2014. The new ARMv8 architecture adds 64-bit memory addressing, increases the number of general purpose registers to 30, and increases the size of the vector registers for NEON/SIMD operations. The Cortex-A57 and A-53 are both aimed at the mobile market. Partners that've already signed on to build ARMv8-based hardware include Samsung, AMD, Broadcom, Calxeda, and STMicro."
The 64-bit ARM ISA is pretty interesting: it's more of wholesale overhaul than a set of additions to the 32-bit ISA.