Although the chances of the Heartbleed bug being exploited through BlackBerry Link was minimal, the desktop app for Windows and Mac had until yesterday remained on BlackBerry's vulnerable list. The good news though, if you were worried about it is that new versions that patch the exploit are now available for download as confirmed by BerryReview.
You can either grab the updates directly from the BlackBerry site using the links above or make use of the auto update feature within BlackBerry Link. Other than the patching for Heatbleed, there doesn't appear to be any other changes but we're still looking for the full change log.