There should be an Update function, maybe under Help, called “Check for Updates” and if Updates are available, Blender asks the user if he wants to update or not.
For users like me, who ALWAYS keep Blender updated, maybe even add an option in the user preferences to automatically check for updates and install them on startup and options for advanced users like “Reset user preferences”, “Clear Bookmarks and Recent Files” and “Change installation path” etc.
I personally don’t mind visiting “https://builder.blender.org/download/” every day, download zip files and overwrite the old files to keep Blender 2.8 up to date, but from my perspective such an update function would increase the user friendliness Blender 2.8 is aiming for.