Move Site into Folder - Bug or Feature?

When I drag and drop a site in the Favorites Manager to a folder (within the same pane), I was expecting it to "move" but it just copies it. Is this a bug or an intended feature? Using x64 XP with your newest version available.

A drag&drop operation within the same drive should result in a move operation.

Did you restart your computer after the installation of the new version?