You can subscribe to the daily or weekly updates from Sprintr which will send you an overview of all new feedback items.
You receive these by default AFAIK.
Separate answer: Tim, to subscribe to updates, navigate to this page:
and click the edit button. You will then have these options:
There used to be a Mendix App Service for Feedback, which I don't see in the app store anymore.
However, you can integrate with the Feedback API using a webservice. The link to the WSDL can be found on this page: https://docs.mendix.com/apidocs-mxsdk/apidocs/feedback-api which also documents how to use the Feedback API. Define a web service in the modeler using the WSDL and follow the directions and you should be able to build a feedback polling service quickly. If you want to, you could send emails or other notifications to users when new feedback items are created (without waiting until the end of the day for the daily digest). I did this on one of my projects using the Feedback App Service and it worked well...didn't take much work.
Hope that helps,