I didn't say they were executing on that strategy well these days. Surface, Zune and Bing are all examples of fast-follower products that either came too late to be relevant (Zune) or that weren't good enough relative to the competition to displace them (Surface, Bing).

Which is not to say they can't execute a fast-follower play successfully anymore -- see XBox and Azure. Just that they don't nail it as thoroughly and consistently as they used to.