The company has done that before, most recently last year. Until June 2010, it provided security updates for Windows 2000 in addition to XP, Vista and Windows 7.
But one analyst argued that Microsoft may need to pick up the pace even more, a move that would increase the number of editions that must be supported.
"They're dealing with two competitors, one the hyper-iterative Google, which seems to always be updating its software," said Wes Miller, an analyst with Directions on Microsoft, in an interview last week.
"The other is Apple, which is logistically iterative," said Miller. "They update almost by clockwork."
Apple annually updates iOS, the mobile operating system that powers the iPad, and has upgraded Mac OS X approximately every two years since 2003.
"You're in a constant race now," said Miller of software development. "I'm not sure if every three years is often enough."