I have an InfoPath form that is used as a SharePoint 2007 content type. My client would like to be able to search fields, so I would like to re-publish and promote some of the fields. Will this cause any loss of data for previously submitted forms? Will data in the previously submitted forms be affected by this promotion? (will data be viewable in SharePoint columns?)
Data won't be lost unless the form field structure is changed in such a way that InfoPath can no longer match the form up to the latest version of the template. For example, adding fields is no problem, and certainly promoting additional fields without changing anything else will be fine.
Previously submitted forms won't show the newly promoted columns in SharePoint views. For this to happen the older forms have to be opened in InfoPath again (note: only opened, they don't have to be saved).
(Tested against InfoPath client not Forms Services.)