In addition to Time Machine I do a weekly clone of my system drive to a volume on a second hard drive in my 2011 MacBook Pro. I also made a clone in another volume before I upgraded to Lion.
Now some of the apps from the Snow Leopard drive clone are starting to show up as duplicates in "open with" contextual menus. If I choose one of the duplicates it will open the app from the cloned volume.
How can I remove these items from the menu and make sure OS X doesn't think these are installed apps?