"You can turn individual chats off the record [unsaved]," Google's help pages say. "But you'll no longer have the option to turn chat history off for all of your chats." The same goes for Hangouts. You can disable individual Hangouts archiving, but there's no universal setting to stop all Hangouts from being archived.
All of this suggests to me that an SMS-integrated Hangouts may want to archive your mobile phone messaging, and it may not be so easy to stop the app from doing so.
But this is all speculation for now! We won't have any real answers until Google (maybe) finally reveals Hangouts 1.3 in the coming months. Nevertheless, it's worth pondering where Google might be headed with Hangouts--and whether that future means more or less control for individual users.
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