Apparently, ADE has become common enough that some stores that previous carried "PDF" files are now listing "Adobe Digital Editions" files.
Got my gaming-ebooks newsletter; clicked on one of this week's freebies--Three Black Crows, Three Dead Men
--and found it's listed as "Product Format: Adobe Digital Edition." I thought, what? They've always had PDFs before. Almost always, letter-sized PDFs, image-heavy, hard to read on portable readers. Suitable for printing, or for keeping on the laptop for search purposes while you have the paper version in front of you.
It's a PDF. An unlocked, no-DRM PDF.
I want stores to stop using program names as filetypes. Or device names as filetypes. There's no such thing as a "Kindle" ebook. Nor a "Nook" ebook. Nor a "Microsoft" ebook. (In my experience, people who tell me they have "Microsoft" ebooks don't usually mean .lit; they mean .doc or .rtf, because when they click on it, it opens "Microsoft.") (And I'm also really tired of people telling me they opened their PDFs in "Adobe," but that's a different rant.)
I suppose there's not much I can do about it, other than expect to have to send emails to new ebook stores to find out what filetypes they actually carry.