Weaselboy, Two things:
(1) I should make a copy of Mavericks Installer DMG before upgrade to create bootable installer.
(2) " you make a Time Machine backup to a locally attached external after your Mavs install, it places a copy of that Recovery HD partition on the Time Machine disk also." Does this work with Mountain Lion install? Or this is just one of the new features with Maveicks.
1) Make the bootable USB key before you install the update or the DMG will get erased. So after the DL from the App Store is done just follow this process to make the installer. Afterward you can just eject your USB key and set it aside then run the installer from your Applications folder to install Mavs.
2) This actually started with Lion 10.7.2. So Lion, Mt. Lion and Mavs all have this.