The same rules apply. If you upgrade Windows 8 to Windows 8.1 Preview you will have to reinstall all your desktop and Windows Store applications once you upgrade the Windows 8.1 Preview to Windows 8.1 RTM. Every single one of those FAQ applies to both Windows RT and Windows 8.
The important information is the following statement.
When you install subsequent editions of Windows 8.1 you'll be able to
keep your personal files, but you'll need to reinstall your apps.
If upgrade to Windows 8.1 by using the Windows Store update or you use a Windows 8.1 RTM installation media you will keep all your personal files, settings, and installed applications. Any Windows Store applications in either case will be downloaded again and be updated as required.