Chris Cornell Performs On Letterman [VIDEO]

Chris Cornell is set to begin his acoustic tour and made a stop on the Late Show with David Letterman last night to perform his latest single, "The Keeper".   The song will be part of a soundtrack for the new movie Machine Gun Preacher starring Gerard Butler and is out in theaters today.  The mellow tune is way different than the sound that can be expected on the upcoming Soundgarden album, which is reportedly very heavy.