Skype has been slowly getting more and more integrated with Microsoft products as Microsoft's old Messenger app has been faded out. With Windows 8.1, Messenger will officially be replaced and Skype will become the default messenger app for the platform. And, as the default messenger app, it will be placed front-and-center on the Start screen, so users know they don't have to download it.
Skype didn't go into detail on if the app would be more deeply integrated with other apps, but we certainly wouldn't be surprised. The Windows 8.1 update will be pushed out starting October 17th, and will be available in retail on October 18th.