Upcoming processors based on ARMv8 will make ARM more competitive in the processor market as it tries to compete with Intel, said Nathan Brookwood, principal analyst at Insight 64.

"Fundamentally, 64-bit capability for ARM is a step to get serious traction with Windows," Brookwood said.

The initial ARM processors on tablets running Windows 8 will be 32-bit, but the ARMv8 announcement assures customers that 64-bit processors are on the way, said Mercury Research's McCarron. Windows versions for 64-bit ARM processors may be delivered through version updates or service packs.

"It doesn't necessarily result in more acceptance, but keeps ARM more competitive," McCarron said.

The transition from 32-bit to 64-bit on tablets and smartphones will be quicker than it was on PCs because most software development for ARM takes place on Linux, McCarron said. The transition from 32-bit to 64-bit on x86 took a long time partly due to backward compatibility issues, with some code stretching back many years.