Following the discussion in this forum post and the formal RFC period, voting has started for denomination=latter_day_saint at the proposal’s wiki page
I originally tried to open voting on Aug 28, until I found out that my message to the tagging mailing list about the RFC was not received. The RFC notification was forwarded to the tagging mailing list on my behalf on Aug 30, so the required two weeks have passed and voting can begin for real now.
Please, cross post this announcement to the tagging mailing list on my behalf by sending an email to: tagging@openstreetmap.org