Long story short, all Propeller servers are patched. As reported, the Heartbleed bug risked exposing encrypted data on websites using OpenSSL. This would have affected a number of Propeller clients had we not responded quickly. As soon as the patch was released, we applied it.
Part of the vulnerability of this bug was that it would enable an intruder to capture data in memory plus the certificate "key". As the name suggests, the key provides secure access. Therefore, we are taking the additional precautionary step of "re-keying" each SSL certificate.
To verify that your site is clean, you can go to this site and enter your website's url: http://filippo.io/Heartbleed/