I know, I hate that acronym, too, but it's so much easier than typing out the entire phrase, "Save the Date." So I succumb to convenience.
I've flip-flopped so many times about what to do for my STD announcement. (Wow, that sounds even worse than just using "STD.") I had a lot of options that I liked, but none that I loved. Then I found this little piece of art on Weddingbee:
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That's it, I'm hooked. I think I can probably do this. We'll see.