Foley heard from her sources that the Start Menu won't be coming with Windows 8.1 Update 2 in August after all as Microsoft decided to hold off on delivering it until the next "major" release of Windows, which is codenamed Threshold.
Microsoft's operating systems group has decided to hold off on delivering a Microsoft-developed Start Menu until Threshold, the next "major" release of Windows. Threshold, which may or may not ultimately be called Windows 9, is expected to be released in April 2015. I'm not clear whether the postponement is because the feature won't be fully baked in time, or if there's another reason for the change in plans.
Microsoft still is moving full steam ahead with plans to try to make Windows 8.x more palatable and usable by those using mice and keyboards, as well as those used to previous Windows iterations. That strategy hasn't changed.