According to a new report from The Verge, Microsoft is planning to merge the Windows Phone Store and Windows 8 Store into one store which will be shared across platforms. The source claims that this change will be apparent in the next release of Windows and Windows Phone, which is expected to be Windows Phone 8.1 and Windows 8.1 GDR 2014.
Right now, information is scarce as to how the app store will work across devices. It's possible that Microsoft are planning to allow Windows Phone apps to run on Windows 8.1 machines, much like how Apple does with it's iPhone apps on iPad.
If so, this is the first step towards a much more unified platform between both Windows and Windows Phone. Microsoft has been talking about unifying the app base between Windows and Windows Phone for some time now, but we are yet to see anything come to light.
Of course, as this information comes from unofficial sources, we ask you to read with a pinch of salt.