The ARMv8 architecture extends the hardware platform to 64-bit. This increase is mostly useful to address massive amounts of memory but can also have other benefits for performance. I think many of us remember the excitement prior to x86-64 and the subsequent let-down when we realized that, for most applications, typical vector extensions kept up in performance especially considering the compatibility issues of the day. It needed to happen but it was a hard sell until… it was just ubiquitous.
AMD has not kept it secret that they are developing 64-bit ARM processors for data centers but, until this week, further details were scarce. Under the codename, "Seattle", these processors will be available in four and eight cores. The Opteron branding will expand beyond x86 to include these new processors. The pitch to enterprises is simple: want both ARM and x86? Why bother with two vendors!
Seattle will also support up to 128GB of ECC memory and 10 Gigabit Ethernet for dense, but power efficient, compute clusters. It will be manufactured on the 28nm process.
The majority of AMD's blog post proclaimed its commitment to software support and it is definitely true that they hold a very high status in both the Linux and Apache Foundations. ARMv8 is supported in Linux starting with kernel 3.7.
Seattle is expected to launch in the second half of 2014.