I just saw for the first time a feed with the filename
rss.xml that’s actually an Atom feed.
That won’t confuse NetNewsWire (which doesn’t care about the filename when determining which parser to use)—but it could be confusing to, well, people.
I’m not going to link to it, because I don’t want to embarrass anybody, but I do want to point it out in case this is the first data point in a trend. (Heck, maybe there are thousands of these already, and this is just the first one I’ve noticed.)
My concern is that the term
RSS could come to mean syndication-in-general, including Atom. I don’t think advocates of Atom or of RSS want that to happen. (Though I could be wrong.)