Is possible to set auto refresh for the Shared Links sidebar in the new Safari 7. There's in "View" menu > Refresh Shared Links, but this doesn't have a shortcut to refresh. So either a way to have the list auto-refresh or assigning a shortcut would help.
This has been fixed in Safari 7.0.1 (which is included in OS X 10.9.1):
About the update
The OS X Mavericks v10.9.1 Update is recommended for all OS X Mavericks users. It improves the stability, compatibility, and security of your Mac. This update includes:
Includes Safari 7.0.1
Updates Shared Links periodically when open in the Safari Sidebar
You can add a shortcut for any menu items in System Preferences > Keyboards > Shortcuts > App Shortcuts