Changes made on this beta preview may not be kept. Changes to photos DEFINITELY won't be.
I don't understand what "changes made on this beta preview may not be kept. Changes to photos definitely won't" means. Can you explain that Brian.
Referring to the first line of the topic post, which reads:
If you go to rc.catholicmatch.com you can see some changes that will be coming out today or tomorrow.
The link which displays the new profile format is the "beta preview". The statement you asked about means that if you make changes to the text content of your profile while viewing that beta preview site those changes may not be retained when the new profiles are moved to the live production system; if you change any photos while using the beta preview they definitiely will not be moved over.
You can tell whether you are using the live system or the beta preview by looking at the browser address bar: the URL of the live system begins with " http://www.catholicmatch.com"; the beta preview begins with "rc.catholicmatch.com" ('rc' being the significant distinguishing characteristic).
I hope this helps.