Using the sharing widget of Jet Pack in Twenty Thirteen the sharing widget doesn't show under the gallery like it does on all other posts.
See Post Format Gallery Screenhot: http://cl.ly/image/1B3f2A1A051y
(It does so on the single post format page, just not the front or search pages event though the search pages are clicked.)
But it does seem to show in Post Format Quote and Page.
See Screenshot: http://cl.ly/image/0X1t120A360l
further note: I did see this on the my own child theme on my own website. http://robertdall.com/ But I checked it with Twenty Thirteen as well.
I am not sure if this is a Twenty Thirteen or Jetpack Issue. But I though I would start here first.