Our upgrade from 7.2.1 to 7.2.3 for our Zimbra Hosting farm completed successfully, but we noticed that the links in the Admin Console to the new ZCO continue to reference the old 7.1.3 ZCO, and that the old ZCO was not removed by the upgrade installer.

We filed a bug report Bug 81395 – Wrong Links for ZCO Downloads

Hope that helps,